Bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/blossom-ci.yml

@@ -51,7 +51,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           repository: ${{ fromJson(needs.Authorization.outputs.args).repo }}
           ref: ${{ fromJson(needs.Authorization.outputs.args).ref }}

.github/workflows/codeql-analysis.yml

@@ -38,7 +38,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.github/workflows/conda.yml

@@ -32,7 +32,7 @@ jobs:
         minimum-size: 8GB
         maximum-size: 16GB
         disk-root: "D:"
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Clean up disk space
       run: |
         find /opt/hostedtoolcache/* -maxdepth 0 ! -name 'Python' -exec rm -rf {} \;

.github/workflows/cron-ngc-bundle.yml

@@ -17,7 +17,7 @@ jobs:
     if: github.repository == 'Project-MONAI/MONAI'
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python 3.9
       uses: actions/setup-python@v6
       with:

.github/workflows/cron.yml

@@ -32,7 +32,7 @@ jobs:
       options: "--gpus all"
     runs-on: [self-hosted, linux, x64, common]
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: apt install
       run: |
         apt-get update
@@ -82,7 +82,7 @@ jobs:
       options: "--gpus all"
     runs-on: [self-hosted, linux, x64, integration]
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Install APT dependencies
       run: |
         apt-get update
@@ -131,7 +131,7 @@ jobs:
       options: "--gpus all"
     runs-on: [self-hosted, linux, x64, integration]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - name: Install the dependencies
@@ -233,7 +233,7 @@ jobs:
       options: "--gpus all --ipc=host"
     runs-on: [self-hosted, linux, x64, integration]
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Install MONAI
       id: monai-install
       run: |

.github/workflows/docker.yml

@@ -21,7 +21,7 @@ jobs:
     if: ${{ false }}  # disable docker build job  project-monai/monai#7450
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         # full history so that we can git describe
         with:
           ref: dev
@@ -53,7 +53,7 @@ jobs:
     needs: versioning_dev
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         ref: dev
     - name: Download version

.github/workflows/integration.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: [self-hosted, linux, x64, command]
     steps:
     # checkout the pull request branch
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         token: ${{ secrets.PR_MAINTAIN }}
         repository: ${{ github.event.client_payload.pull_request.head.repo.full_name }}
@@ -89,7 +89,7 @@ jobs:
     runs-on: [self-hosted, linux, x64, command1]
     steps:
     # checkout the pull request branch
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         token: ${{ secrets.PR_MAINTAIN }}
         repository: ${{ github.event.client_payload.pull_request.head.repo.full_name }}

.github/workflows/pythonapp-gpu.yml

@@ -44,7 +44,7 @@ jobs:
       options: --gpus all --env NVIDIA_DISABLE_REQUIRE=true  # workaround for unsatisfied condition: cuda>=11.6
     runs-on: [self-hosted, linux, x64, common]
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: apt install
       if: github.event.pull_request.merged != true
       run: |

.github/workflows/pythonapp-min.yml

@@ -30,7 +30,7 @@ jobs:
         os: [windows-latest, macOS-latest, ubuntu-latest]
     timeout-minutes: 40
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python 3.9
       uses: actions/setup-python@v6
       with:
@@ -79,7 +79,7 @@ jobs:
         python-version: ['3.9', '3.10', '3.11', '3.12']
     timeout-minutes: 40
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v6
       with:
@@ -128,7 +128,7 @@ jobs:
         pytorch-version: ['2.5.1', '2.6.0', '2.7.1', '2.8.0']
     timeout-minutes: 40
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python 3.9
       uses: actions/setup-python@v6
       with:

.github/workflows/pythonapp.yml

@@ -28,7 +28,7 @@ jobs:
       matrix:
         opt: ["codeformat", "pytype", "mypy"]
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python 3.9
       uses: actions/setup-python@v6
       with:
@@ -70,7 +70,7 @@ jobs:
         minimum-size: 8GB
         maximum-size: 16GB
         disk-root: "D:"
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python 3.9
       uses: actions/setup-python@v6
       with:
@@ -129,7 +129,7 @@ jobs:
       QUICKTEST: True
       shell: bash
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
       with:
         fetch-depth: 0
     - name: Set up Python 3.9
@@ -213,7 +213,7 @@ jobs:
   build-docs:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python 3.9
       uses: actions/setup-python@v6
       with: