Add include-only-assigned to the action.yml (#824)

Author: JoannaaKL

action.yml

@@ -196,6 +196,10 @@ inputs:
     description: 'Any update (update/comment) can reset the stale idle time on the pull requests. Override "ignore-updates" option regarding only the pull requests.'
     default: ''
     required: false
+  include-only-assigned:
+    description: 'Only the issues or the pull requests with an assignee will be marked as stale automatically.'
+    default: 'false'
+    required: false
 outputs:
   closed-issues-prs:
     description: 'List of all closed issues and pull requests.'