Update gradle/actions action to v6 (#352)

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

Author: renovate[bot]

.github/workflows/main.yml

@@ -40,7 +40,7 @@ jobs:
         if: matrix.jdk.version != '17'
         shell: bash
         run: echo "TOOLCHAIN_JDK=$JAVA_HOME" >> $GITHUB_ENV
-      - uses: gradle/actions/setup-gradle@0723195856401067f7a2779048b490ace7a47d7c # v5.0.2
+      - uses: gradle/actions/setup-gradle@0f4528296b4bc09e8ae0fc7be30185a4ab435545 # v6.0.0
         with:
           cache-encryption-key: ${{ secrets.GRADLE_ENCRYPTION_KEY }}
       - uses: testlens-app/setup-testlens@0232fb63c43e5b93421545ba67bbb2981790a87f # v1.8.0
@@ -80,7 +80,7 @@ jobs:
       - name: 'Prepare TOOLCHAIN_JDK env var'
         shell: bash
         run: echo "TOOLCHAIN_JDK=$JAVA_HOME" >> $GITHUB_ENV
-      - uses: gradle/actions/setup-gradle@0723195856401067f7a2779048b490ace7a47d7c # v5.0.2
+      - uses: gradle/actions/setup-gradle@0f4528296b4bc09e8ae0fc7be30185a4ab435545 # v6.0.0
         with:
           cache-encryption-key: ${{ secrets.GRADLE_ENCRYPTION_KEY }}
       - shell: bash
@@ -109,7 +109,7 @@ jobs:
         with:
           distribution: liberica
           java-version: 17
-      - uses: gradle/actions/setup-gradle@0723195856401067f7a2779048b490ace7a47d7c # v5.0.2
+      - uses: gradle/actions/setup-gradle@0f4528296b4bc09e8ae0fc7be30185a4ab435545 # v6.0.0
         with:
           cache-encryption-key: ${{ secrets.GRADLE_ENCRYPTION_KEY }}
       - shell: bash