ci: set up requirements upgrade with uv (#296)

Author: afuetterer

.github/workflows/upgrade-requirements.yml

@@ -0,0 +1,17 @@
+name: Upgrade requirements
+
+on:
+  schedule:
+    # run once a month at midnight of the first day of the month
+  - cron: 0 0 1 * *
+  workflow_dispatch: # run manually from actions tab
+
+# Set permissions at the job level.
+permissions: {}
+
+jobs:
+  upgrade:
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: afuetterer/.github/.github/workflows/_upgrade-requirements.yml@main