Add Github Action for Publishing to Comfy Registry (#2)

This PR adds a Github Action (publish-node-action) that will run
whenever the pyproject.toml file changes. The pyproject.toml defines the
custom node version you want to publish (added in another PR).

Action Required:

- [x] Make sure the trigger branch (`master` or `main`) in
`publish.yaml` matches the branch you want to use as the publishing
branch. It will only trigger when the pyproject.toml gets updated on
that branch.
- [x] Create an api key on the Registry for publishing from Github.
[Instructions](https://docs.comfy.org/registry/overview#create-an-api-key-for-publishing).
- [x] Add it to your Github Repository Secrets as
`REGISTRY_ACCESS_TOKEN`.

More info on the [registry](https://comfyregistry.org/).
Please message me on [Discord](https://discord.com/invite/comfyorg) if
you have any questions!

.github/workflows/publish.yml

@@ -0,0 +1,21 @@
+name: Publish to Comfy registry
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+    paths:
+      - "pyproject.toml"
+
+jobs:
+  publish-node:
+    name: Publish Custom Node to registry
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+      - name: Publish Custom Node
+        uses: Comfy-Org/publish-node-action@main
+        with:
+          ## Add your own personal access token to your Github Repository secrets and reference it here.
+          personal_access_token: ${{ secrets.REGISTRY_ACCESS_TOKEN }}