Bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5...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/angular.yml

@@ -40,7 +40,7 @@ jobs:
         outputs:
             matrix: ${{ steps.build.outputs.matrix }}
         steps:
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
             - uses: actions/setup-node@v6
               with:
                   node-version: 22
@@ -63,7 +63,7 @@ jobs:
             #----------------------------------------------------------------------
             # Install all tools and check configuration
             #----------------------------------------------------------------------
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
               with:
                   path: jhipster-kotlin
                   fetch-depth: 2

.github/workflows/build-cache.yml

@@ -10,7 +10,7 @@ jobs:
             run:
                 working-directory: ${{ github.workspace }}/app
         steps:
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
               with:
                   path: generator-jhipster-kotlin
             - uses: jhipster/actions/setup-runner@v1

.github/workflows/codeql-analysis.yml

@@ -12,7 +12,7 @@ jobs:
 
         steps:
             - name: Checkout repository
-              uses: actions/checkout@v5
+              uses: actions/checkout@v6
               with:
                   # We must fetch at least the immediate parents so that if this is
                   # a pull request then we can checkout the head.

.github/workflows/copyright-update.yml

@@ -17,7 +17,7 @@ jobs:
         timeout-minutes: 40
         steps:
             # Checkout
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
               with:
                   ref: main
                   fetch-depth: 0

.github/workflows/generator.yml

@@ -8,7 +8,7 @@ jobs:
         runs-on: ubuntu-latest
         timeout-minutes: 20
         steps:
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
             - uses: actions/setup-node@v6
               with:
                   node-version: 20

.github/workflows/react.yml

@@ -40,7 +40,7 @@ jobs:
         outputs:
             matrix: ${{ steps.build.outputs.matrix }}
         steps:
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
             - uses: actions/setup-node@v6
               with:
                   node-version: 22
@@ -63,7 +63,7 @@ jobs:
             #----------------------------------------------------------------------
             # Install all tools and check configuration
             #----------------------------------------------------------------------
-            - uses: actions/checkout@v5
+            - uses: actions/checkout@v6
               with:
                   path: jhipster-kotlin
                   fetch-depth: 2