Removed ref from checkout action (#758)

Author: Reedyuk

.github/workflows/pull_request.yml

@@ -16,8 +16,6 @@ jobs:
     runs-on: macos-latest
     steps:
       - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.head_ref }}
       - name: Set up JDK
         uses: actions/setup-java@v4
         with:

.github/workflows/pull_request_target.yml

@@ -15,8 +15,6 @@ jobs:
       contents: write
     steps:
       - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.head_ref }}
       - name: Set up JDK
         uses: actions/setup-java@v4
         with: