added workflow to release packages to maven repo

Author: paullatzelsperger

.github/workflows/publish.yaml

@@ -0,0 +1,27 @@
+# This workflow uses actions that are not certified by GitHub.
+# They are provided by a third-party and are governed by
+# separate terms of service, privacy policy, and support
+# documentation.
+
+name: Publish package to GitHub Packages
+on:
+  release:
+    types: [created]
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-java@v2
+        with:
+          java-version: '11'
+          distribution: 'adopt'
+      - name: Validate Gradle wrapper
+        uses: gradle/wrapper-validation-action@e6e38bacfdf1a337459f332974bb2327a31aaf4b
+      - name: Publish package
+        run: gradle publishAllPublicationToGitHubPackagesRepository
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}