ci: specify a region when talking with aws

Author: pietroalbini

.github/workflows/main.yml

@@ -47,7 +47,7 @@ jobs:
 
       - name: Start the synchronization tool
         run: |
-          aws lambda invoke --function-name start-sync-team output.json
+          aws --region us-west-1 lambda invoke --function-name start-sync-team output.json
           cat output.json | python3 -m json.tool
         env:
           AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}