Actions: Remove synchronize trigger in create-dependabot-issues.yml

Synchronize trigger only necessary to catch up issues with PRs opened before workflow was implemented.
Disables repeat issue creation for same PR.

.github/workflows/create-dependabot-issues.yml

@@ -2,7 +2,7 @@ name: Create Dependabot Issues # from pull requests
 
 on:
   pull_request:
-    types: [opened, synchronize]
+    types: [opened]
     branches: [main]
 
 jobs: