Adding Code Quality workflow

.github/workflows/code_quality_check.yml

@@ -0,0 +1,45 @@
+name: Code Convention Verification
+
+on:
+  push:
+    branches:
+      - "master"
+      - "*-rc"
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+      - "**"
+
+jobs:
+  checkstyle-and-spotless:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Java & Gradle
+        uses: actions/setup-java@v4
+        with:
+          java-version: '17'
+          distribution: 'temurin'
+          cache: 'gradle'
+
+      - uses: actions/cache@v4
+        name: Cache Gradle Wrapper
+        id: cache-gradle-wrapper
+        with:
+          path: |
+            gradle/wrapper/gradle-wrapper.jar
+          key: gradle-wrapper-v1
+
+      - name: Get Gradle wrapper
+        if: steps.cache-gradle-wrapper.outputs.cache-hit != 'true'
+        run: |
+          ./configure.sh
+
+      - name: Run Checkstyle
+        run: |
+          ./gradlew clean rskj-core:checkstyleMain checkstyleTest
+
+      - name: Run Spotless Check
+        run: |
+          ./gradlew clean rskj-core:spotlessCheck