Run Github Actions workflow weekly

Previously, the workflow would run on every push to the repository or
via manual triggering.

With this change, the workflow will also run every Sunday at 8:00 UTC,
which will ensure that the specific AGP used in the recipes are kept up
to date.

Bug: NA
Test: existing
Change-Id: I488581efd82876099acd1ad0ccecf94431eadc30

.github/workflows/convert-recipes.yml

@@ -3,6 +3,8 @@ name: Convert recipes flow
 on:
   push:
   workflow_dispatch:
+  schedule:
+    - cron: '0 8 * * 0' # Run every Sunday at 8:00 UTC
 
 jobs:
   build-gradle-project: