chore: update workflow permissions again (#1191)

once more with feeling

Author: Rich-Harris

.github/workflows/docs-preview-create.yml

@@ -21,8 +21,7 @@ on:
         type: string
 
 permissions:
-  contents: read
-  issues: write
+  contents: write
 
 env:
   BRANCH: preview-${{ inputs.repo }}-${{ inputs.pr }}