Add GH workflow for publishing

.github/workflows/release.yml

@@ -0,0 +1,49 @@
+name: SMBJ Release
+
+on:
+  push:
+    tags:
+      - '*'
+
+permissions:
+  contents: write
+
+jobs:
+  java12:
+    name: Build with Java 12
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - name: Set up JDK 12
+        uses: actions/setup-java@v1
+        with:
+          java-version: 12
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+      - name: Build with Gradle
+        run: ./gradlew check
+  release:
+    name: Release
+    needs: [java12]
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - uses: actions/setup-java@v1
+        with:
+          java-version: 12
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+      - name: Release
+        run: ./gradlew release -Prelease.disableChecks -Prelease.pushTagsOnly -Prelease.customUsername=${{ github.actor }} -Prelease.customPassword=${{ github.token }}
+        env:
+          ORG_GRADLE_PROJECT_signingKey: ${{ secrets.SIGNINGKEY }}
+          ORG_GRADLE_PROJECT_signingKeyId: ${{ secrets.SIGNINGKEYID }}
+          ORG_GRADLE_PROJECT_signingPassword: ${{ secrets.SIGNINGPASSWORD }}
+          ORG_GRADLE_PROJECT_sonatypeUsername: ${{ secrets.OSSRH_USERNAME }}
+          ORG_GRADLE_PROJECT_sonatypePassword: ${{ secrets.OSSRH_PASSWORD }}
+
+