This commit adds one of a pair of GitHub Actions to create a new issue in the documentation repository when a PR with a needs-docs label is merged in the main repository. This is intended to support improved documentation.

Additional steps required

1. In order to work, the related PR in the documentation repository will also need to be merged, as it contains a job that actually creates the issue. The action in this repository simply triggers an alert and passes information to the other repository.

2. I have created a GitHub bot with the sole purpose of enabling the use of authorisation tokens with tightly-scoped permissions owned by the organization rather than an individual. We need this because we're triggering an action in one repository to do trigger another action in a different repository.

Ownership has been transferred to `bookwyrm-social`. A new private key should be generated, and the `APPLICATION_ID` and `APPLICATION_PRIVATE_KEY` need to be added to the main repository's _Action_ `SECRETS`.

Both repositories (or "All repositories") must be granted access, in the Bot configuration screen.

3. In the main repository settings, _Actions - General_ permissions must be set to _Allow all actions and reusable workflows_.

.github/workflows/trigger_docs_issue.yml

@@ -0,0 +1,30 @@
+name: Repository Dispatch
+on:
+  pull_request:
+    types: [closed]
+jobs:
+  dispatch:
+    if: github.event.pull_request.merged == true && contains(github.event.pull_request.labels.*.name, 'needs-docs')
+    runs-on: ubuntu-latest
+    steps:
+      - name: authenticate
+        id: get_workflow_token
+        uses: peter-murray/workflow-application-token-action@v3
+        with:
+          application_id: ${{ secrets.APPLICATION_ID }}
+          application_private_key: ${{ secrets.APPLICATION_PRIVATE_KEY }}
+
+      - name: dispatch
+        uses: peter-evans/repository-dispatch@v3
+        env:
+          DOCS_TOKEN: ${{ steps.get_workflow_token.outputs.token }}
+        with:
+          token: ${{ env.DOCS_TOKEN }}
+          repository: bookwyrm-social/documentation
+          event-type: docs-needed
+          client-payload: |-
+            {
+              "title": "${{ github.event.pull_request.title }}",
+              "body": ${{ toJson(github.event.pull_request.body) }},
+              "number": "${{ github.event.number }}"
+            }