fix: update the trigger for github workflow from pull_request_target to pull_request as the vulnerability fixes due to caching of poetry.lock were not getting addressed

Author: nshalabh

.github/workflows/safety.yml

@@ -1,7 +1,7 @@
 name: safety - Python Dependency Check
 
 on:
-  pull_request_target:
+  pull_request:
     branches:
       - main
   push: