limit workflows to main repo

Author: jertel

.github/workflows/close-threads.yml

@@ -15,6 +15,7 @@ concurrency:
 
 jobs:
   close-threads:
+    if: github.repository_owner == 'jertel'
     runs-on: ubuntu-latest
     permissions:
       issues: write

.github/workflows/lock-threads.yml

@@ -15,6 +15,7 @@ concurrency:
 
 jobs:
   lock-threads:
+    if: github.repository_owner == 'jertel'
     runs-on: ubuntu-latest
     steps:
       - uses: jertel/lock-threads@main