Update various external GitHub CI actions (#1869)

Author: liblit

.github/workflows/continuous-integration.yml

@@ -44,7 +44,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Check out WALA sources
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: 'Set up JDKs'
         uses: actions/setup-java@v5
         with:
@@ -58,7 +58,7 @@ jobs:
             26
           distribution: 'zulu'
       - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@v4
+        uses: gradle/actions/setup-gradle@v6
       - name: Choose extra Linux-only Gradle tasks
         run: echo OS_SPECIFIC_GRADLE_TASKS='publishAllPublicationsToFakeRemoteRepository shellcheck' >> $GITHUB_ENV
         if: runner.os == 'Linux'
@@ -72,7 +72,7 @@ jobs:
             aggregatedJavadocs javadoc build ${{ env.OS_SPECIFIC_GRADLE_TASKS }} checkGitCleanliness
       - name: Upload test results
         if: always()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: Test results for JDK ${{ matrix.java }} on ${{ matrix.os }}
           path: |
@@ -93,7 +93,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Upload event file
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: Event file
           path: ${{ github.event_path }}
@@ -106,14 +106,14 @@ jobs:
       JDK_VERSION: 26
     steps:
       - name: 'Check out repository'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: 'Set up JDK'
         uses: actions/setup-java@v5
         with:
           java-version: ${{ env.JDK_VERSION }}
           distribution: 'zulu'
       - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@v4
+        uses: gradle/actions/setup-gradle@v6
       - name: 'Generate latest docs'
         env:
           GITHUB_TOKEN: ${{ secrets.WALA_BOT_GH_TOKEN }}