feat: CI to publish artefacts on release

Author: NishkarshRaj

.github/workflows/npm-publish.yml

@@ -0,0 +1,35 @@
+name: Release Backstage GitHub Plugin
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 16
+      - run: |
+          npm i -g yarn
+          yarn install
+          yarn tsc
+
+  publish-npm:
+    needs: validate
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 16
+          registry-url: https://registry.npmjs.org/
+      - run: |
+          yarn install
+          yarn tsc
+          yarn build
+          npm publish
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.npm_token}}