ci: skip scheduled workflows on forks

Add `if: github.repository == 'BerriAI/litellm'` guard to scheduled
jobs in stale.yml, codeql.yml, and create_daily_staging_branch.yml.

This matches the existing pattern in auto_update_price_and_context_window.yml
and prevents these workflows from running unnecessarily on fork repositories.

.github/workflows/codeql.yml

@@ -15,6 +15,7 @@ concurrency:
 
 jobs:
   analyze:
+    if: github.repository == 'BerriAI/litellm'
     name: Analyze (${{ matrix.language }})
     runs-on: ubuntu-latest
     timeout-minutes: 30

.github/workflows/create_daily_staging_branch.yml

@@ -7,6 +7,7 @@ on:
 
 jobs:
   create-staging-branch:
+    if: github.repository == 'BerriAI/litellm'
     runs-on: ubuntu-latest
 
     steps:
@@ -43,6 +44,7 @@ jobs:
           fi
 
   create-internal-dev-branch:
+    if: github.repository == 'BerriAI/litellm'
     runs-on: ubuntu-latest
 
     steps:

.github/workflows/stale.yml

@@ -7,6 +7,7 @@ on:
 
 jobs:
   stale:
+    if: github.repository == 'BerriAI/litellm'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/stale@v8