Add workflow_dispatch trigger to scorecard.yml

Allows us to manually run the workflow.

.github/workflows/scorecard.yml

@@ -13,6 +13,7 @@ on:
     - cron: '43 12 * * 6'
   push:
     branches: [ "main" ]
+  workflow_dispatch:
 
 # Declare default permissions as read only.
 permissions: read-all