Bump actions/checkout from 6 to 7 (#3147)

Bumps [actions/checkout](https://github.com/actions/checkout) from 6 to 7.
- [Release notes](https://github.com/actions/checkout/releases)
- [Commits](actions/checkout@v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/check-deprecated-exercises.yml

@@ -14,7 +14,7 @@ jobs:
     name: Check for deprecated exercises
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
         with:
           fetch-depth: 0
       - name: Test deprecated exercises using test-deprecated-exercises

.github/workflows/create-configlet-sync-issues.yml

@@ -19,7 +19,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Fetch configlet
         run: ./bin/fetch-configlet

.github/workflows/java.yml

@@ -16,7 +16,7 @@ jobs:
     if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
       - name: Set up JDK 25
         uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654
         with:
@@ -31,7 +31,7 @@ jobs:
     if: github.event_name == 'pull_request'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
         with:
           fetch-depth: 0
       - name: Set up JDK 25
@@ -47,7 +47,7 @@ jobs:
     if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
       - name: Set up JDK 25
         uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654
         with:
@@ -62,7 +62,7 @@ jobs:
     if: github.event_name == 'pull_request'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
         with:
           fetch-depth: 0
       - name: Set up JDK 25
@@ -78,7 +78,7 @@ jobs:
     if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
       - name: Test all exercises using java-test-runner
         run: bin/test-with-test-runner
       - name: Print summary
@@ -105,7 +105,7 @@ jobs:
     if: github.event_name == 'pull_request'
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
         with:
           fetch-depth: 0
       - name: Test changed exercises using java-test-runner

.github/workflows/markdown.yml

@@ -17,6 +17,6 @@ jobs:
     name: Lint Markdown files
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0
       - name: Lint markdown
         uses: DavidAnson/markdownlint-cli2-action@ded1f9488f68a970bc66ea5619e13e9b52e601cd