feat: publish beta and development tags on npm (#4769)

* feat: add logic to publish beta/dev npm

This adds new log to publish the npm package both while working on PRs and when
PRs are merged into main, allowing us to easily test changes in a
production-like setting.

Co-authored-by: Asher <ash@coder.com>

.github/workflows/npm-dev.yaml

@@ -0,0 +1,27 @@
+name: Publish on npm and tag with "beta"
+
+on:
+  # Shows the manual trigger in GitHub UI
+  # helpful as a back-up in case the GitHub Actions Workflow fails
+  workflow_dispatch:
+
+  push:
+    branches:
+      - main
+
+jobs:
+  # NOTE: this job requires curl, jq and yarn
+  # All of them are included in ubuntu-latest.
+  npm:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Run ./ci/steps/publish-npm.sh
+        run: yarn publish:npm
+        env:
+          ENVIRONMENT: "staging"
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
+          NPM_TAG: "beta"
+          PR_NUMBER_AND_COMMIT_SHA: ${{ github.event.number }}-${{ github.event.pull_request.head.sha }}