Add workflow used to automatically create GitHub releases

The new workflow uses a "RELEASE" file to create, when required, new
release tags and GitHub releases. It uses the following GutHub action:

https://github.com/pipe-cd/actions-gh-release

---

With this in place, the release strategy would be to:
- publish to npm locally. As part of publishing, the package's
  version will be stepped in package.json. Create a commit for
  that change and also add/update the RELEASE file (*) with
  corresponding tag.
- push that commit for review to the GitHub project
  - The GitHub action will add a preview of the Github release
    to be created upon merging
- once merged, the new tag and automatically-generated
  GitHub release will be created, that correspond to the
  published npm pacakge

(*) https://github.com/pipe-cd/actions-gh-release#usage

Signed-off-by: Marc Dumais <[email protected]>

.github/workflows/gh-release.yml

@@ -0,0 +1,24 @@
+on:
+    push:
+      branches:    
+        - main
+      paths:
+        - 'RELEASE'
+    pull_request:
+      types: [opened, synchronize]
+      branches:
+        - main
+      paths:
+        - 'RELEASE'
+
+jobs:
+  gh-release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - uses: pipe-cd/[email protected]
+        with:
+          release_file: 'RELEASE'
+          token: ${{ secrets.GITHUB_TOKEN }}