Bump gradle/gradle-build-action from 2.5.1 to 2.6.0 (#74)

Bumps [gradle/gradle-build-action](https://github.com/gradle/gradle-build-action) from 2.5.1 to 2.6.0.
- [Release notes](https://github.com/gradle/gradle-build-action/releases)
- [Commits](gradle/gradle-build-action@v2.5.1...v2.6.0)

---
updated-dependencies:
- dependency-name: gradle/gradle-build-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/gradle-build.yml

@@ -31,7 +31,7 @@ jobs:
         distribution: zulu
         java-version: 11
     - name: Setup Gradle
-      uses: gradle/gradle-build-action@v2.5.1
+      uses: gradle/gradle-build-action@v2.6.0
     - run: ./gradlew check
       id: gradle
     - name: Coveralls