Bump gradle/gradle-build-action from 2.7.1 to 2.8.0 (#141)

Bumps [gradle/gradle-build-action](https://github.com/gradle/gradle-build-action) from 2.7.1 to 2.8.0.
- [Release notes](https://github.com/gradle/gradle-build-action/releases)
- [Commits](gradle/gradle-build-action@v2.7.1...v2.8.0)

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

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

.github/workflows/ci-build.yml

@@ -18,5 +18,5 @@ jobs:
           distribution: zulu
           java-version: 11
       - name: Set up Gradle
-        uses: gradle/gradle-build-action@v2.7.1
+        uses: gradle/gradle-build-action@v2.8.0
       - run: "./gradlew :check"

.github/workflows/gh-pages.yml

@@ -29,7 +29,7 @@ jobs:
           distribution: zulu
           java-version: 11
       - name: Set up Gradle
-        uses: gradle/gradle-build-action@v2.7.1
+        uses: gradle/gradle-build-action@v2.8.0
       - run: "./gradlew :asciidoctor"
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v2

.github/workflows/release.yml

@@ -17,7 +17,7 @@ jobs:
           distribution: zulu
           java-version: 11
       - name: Set up Gradle
-        uses: gradle/gradle-build-action@v2.7.1
+        uses: gradle/gradle-build-action@v2.8.0
       - run: "./gradlew :publishPlugin --no-configuration-cache"
         env:
           SIGNING_KEY: ${{ secrets.SIGNING_KEY }}