ci: enable fixdiscover automation

.github/dependabot.yml

@@ -0,0 +1,8 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly
+    labels:
+      - github_actions

.github/workflows/fixdiscover.yml

@@ -0,0 +1,24 @@
+name: FixDiscover for finding backport candidates in systemd JIRA issues
+on:
+  schedule:
+    # Workflow runs every week on sunday at 23:00 UTC
+    - cron: '0 23 * * 0'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  fixdiscover:
+    if: github.repository == 'redhat-plumbers/.github'
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 'lts/*'
+
+      - run: npx fixdiscover --component systemd
+        env:
+          JIRA_API_TOKEN: ${{ secrets.JIRA_API_TOKEN }}
+          GITHUB_API_TOKEN: ${{ secrets.GITHUB_TOKEN }}