Add release action

Author: boardfish

.github/workflows/release.yml

@@ -0,0 +1,31 @@
+name: 'Release'
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  release:
+    if: startsWith(github.ref, 'refs/tags/v')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Build Changelog
+        id: github_release
+        uses: mikepenz/release-changelog-builder-action@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Create Release
+        uses: actions/create-release@v1
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          body: ${{steps.github_release.outputs.changelog}}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - uses: actions/checkout@v1
+      - name: Release Gem
+        uses: cadwallion/publish-rubygems-action@master
+        env:
+          GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}
+          RUBYGEMS_API_KEY: ${{secrets.RUBYGEMS_API_KEY}}
+          RELEASE_COMMAND: rake release