CI: bump actions/checkout to v5

Author: masterkain

.github/workflows/release.yml

@@ -13,7 +13,7 @@ jobs:
   release:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Set up Ruby
         uses: ruby/setup-ruby@v1
         with:

.github/workflows/test.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Set up Environment Variables
         run: |
           echo "ACTIVEMODEL_VERSION=${{ matrix.activemodel }}" >> $GITHUB_ENV
@@ -56,7 +56,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Set up Environment Variables
         run: |
           echo "AR_INTEGRATION=1" >> $GITHUB_ENV