Update actions/checkout action to v7

Author: renovate[bot]

.github/workflows/pull_request.yml

@@ -11,7 +11,7 @@ jobs:
       contents: read
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: actions/setup-java@v5
         with:
           distribution: 'zulu'