Add publish checkstyle report action (#2514)

.github/workflows/build.yml

@@ -15,6 +15,11 @@ jobs:
           fetch-depth: 0
       - uses: gradle/wrapper-validation-action@v1
       - run: ./gradlew check build publishToMavenLocal --stacktrace --warning-mode=fail -Porg.gradle.parallel.threads=4
+      - uses: Juuxel/publish-checkstyle-report@v1
+        if: ${{ failure() }}
+        with:
+          reports: |
+            **/build/reports/checkstyle/*.xml
       - run: mkdir run && echo "eula=true" >> run/eula.txt
       - run: ./gradlew runAutoTestServer --stacktrace --warning-mode=fail
       - uses: actions/upload-artifact@v2