Optimize workflow triggers to prevent unnecessary runs

- Run on pushes to feature branches (exclude main/dev)
- Run on PRs targeting main or dev branches only
- Prevents redundant runs on protected target branches

Author: jake-mahon-netwrix

.github/workflows/validate-branch-history.yml

@@ -4,7 +4,12 @@ on:
   push:
     branches:
       - '**'
+      - '!main'
+      - '!dev'
   pull_request:
+    branches:
+      - main
+      - dev
     types: [opened, synchronize, reopened]
 
 env: