Give explicit permissions to Github actions (#314)

because actions in this repo no longer have write permission by default.

Author: graebm

.github/workflows/closed-issue-message.yml

@@ -5,6 +5,8 @@ on:
 jobs:
     auto_comment:
         runs-on: ubuntu-latest
+        permissions:
+          issues: write
         steps:
         - uses: aws-actions/closed-issue-message@v1
           with:

.github/workflows/stale_issue.yml

@@ -9,6 +9,9 @@ jobs:
   cleanup:
     runs-on: ubuntu-latest
     name: Stale issue job
+    permissions:
+      issues: write
+      pull-requests: write
     steps:
     - uses: aws-actions/stale-issue-cleanup@v3
       with: