Add permissions to the closed PR workflow (#854)

Helps if the GitHub Action is allowed to take its action. :)

Author: SeanKilleen

.github/workflows/closed-pr.yml

@@ -3,6 +3,8 @@ on:
       types: [ closed ]
 jobs:
     prune:
+      permissions: 
+        deployments: write
       runs-on: ubuntu-latest
       steps:
       - name: delete environment