GitHub Actions CI/CD.

.github/workflows/publish_pubdev.yml

@@ -0,0 +1,17 @@
+name: Publish to Pub.dev
+
+on:
+  push:
+    branches: [main]
+
+jobs:
+  publishing:
+    runs-on: ubuntu-latest
+    steps:
+      - name: "Checkout"
+        uses: actions/checkout@v2
+
+      - name: "pos"
+        uses: k-paxian/dart-package-publisher@master
+        with:
+          credentialJson: ${{ secrets.CREDENTIAL_JSON }}