Add ci.yml for auto-publishing gem on version tag

Add ci.yml for auto-publishing gem on version tag

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..41050b2
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,22 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+    tags:
+      - v*
+
+jobs:
+  publish:
+    if: contains(github.ref, 'refs/tags/v')
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Release Gem
+        uses: CvX/publish-rubygems-action@master
+        env:
+          RUBYGEMS_API_KEY: ${{secrets.RUBYGEMS_API_KEY}}

GitHub sha: 2936f544