[88] scheduled build (#89)

Author: voj

.github/workflows/dev.yml

@@ -1,6 +1,8 @@
 name: Dev workflow
 
 on:
+  schedule:
+    - cron:  '40 7 * * 0' # At 07:40 on Sunday
   pull_request:
     branches: [main, deploy-test]
 
@@ -13,4 +15,5 @@ jobs:
     with:
       operating-systems: "['ubuntu-latest']"
       python-versions: "['3.10']"
+      delete-poetry-lock: ${{ github.event_name == 'schedule' }} # the scheduled build tests against newer dependencies
     secrets: inherit