Update autoresponder for pausing community contributions (#37)

We realized belatedly that we should create a shared, re-usable workflow.

This simplifies the workflow logic using a variable for the forum category
that the new topic gets created in, if they click the link to copy their post
from here to the forum.

Author: kytrinyx

.github/workflows/pause-community-contributions.yml

@@ -9,48 +9,13 @@ on:
       - opened
   workflow_dispatch:
 
+permissions:
+  issues: write
+  pull-requests: write
+
 jobs:
   pause:
-    name: Pause Community Contributions
-    runs-on: ubuntu-22.04
-    steps:
-      - name: Detect if user is org member
-        uses: actions/github-script@d556feaca394842dc55e4734bf3bb9f685482fa0
-        id: is-organization-member
-        with:
-          script: |
-            if (context.actor == 'dependabot' || context.actor == 'exercism-bot' || context.actor == 'github-actions[bot]') {
-              return true;
-            }
-
-            return github.rest.orgs.checkMembershipForUser({
-              org: context.repo.owner,
-              username: context.actor,
-            }).then(response => response.status == 204)
-              .catch(err => true);
-      - name: Comment
-        if: steps.is-organization-member.outputs.result == 'false'
-        uses: actions/github-script@d556feaca394842dc55e4734bf3bb9f685482fa0
-        with:
-          script: |
-            const isIssue = !!context.payload.issue;
-            const subject = context.payload.issue || context.payload.pull_request;
-            const thing = (isIssue ? 'issue' : 'PR');
-            const aThing = (isIssue ? 'an issue' : 'a PR');
-            github.rest.issues.createComment({
-              issue_number: context.issue.number,
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              body: `Hello. Thanks for opening ${aThing} on Exercism. We are currently in a phase of our journey where we have paused community contributions to allow us to take a breather and redesign our community model. You can learn more in [this blog post](https://exercism.org/blog/freeing-our-maintainers). **As such, all issues and PRs in this repository are being automatically closed.**\n\nThat doesn’t mean we’re not interested in your ideas, or that if you’re stuck on something we don’t want to help. The best place to discuss things is with our community on the Exercism Community Forum. You can use [this link](https://forum.exercism.org/new-topic?title=${encodeURI(subject.title)}&body=${encodeURI(subject.body)}&category=support) to copy this into a new topic there.\n\n---\n\n_Note: If this ${thing} has been pre-approved, please link back to this ${thing} on the forum thread and a maintainer or staff member will reopen it._\n`
-            })
-      - name: Close
-        if: steps.is-organization-member.outputs.result == 'false'
-        uses: actions/github-script@d556feaca394842dc55e4734bf3bb9f685482fa0
-        with:
-          script: |
-            github.rest.issues.update({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              issue_number: context.issue.number,
-              state: 'closed',
-            })
+    if: github.repository_owner == 'exercism' # Stops this job from running on forks
+    uses: exercism/github-actions/.github/workflows/community-contributions.yml@main
+    with:
+      forum_category: support