Update actions/checkout action to v6 (#140)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/cd.yml

@@ -36,7 +36,7 @@ jobs:
       group: cd-${{ matrix.project.repo }}
     steps:
       - name: Checkout project repo
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           path: project-repo
           repository: ${{ matrix.project.repo }}

.github/workflows/create-or-update-test-pr.yml

@@ -31,7 +31,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout project repo
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           path: project-repo
           repository: ${{ inputs.project_repo }}

template/.github/workflows/ci-{{app_name}}.yml.jinja

@@ -24,7 +24,7 @@ jobs:
     name: Lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       # https://github.com/docker/compose/issues/1973
       - name: Create required env files
@@ -38,7 +38,7 @@ jobs:
     name: Test
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - run: make init-container
       - run: make precompile-assets