OK, will this work? Think the problem is that issues don't set a context

.github/workflows/fetch_sha.yml

@@ -29,7 +29,7 @@ jobs:
         with:
           result-encoding: string
           script: |
-            if (!((context.payload.issue) || (context.payload.pull_request))) {
+            if (!context.payload.pull_request) {
               return context.sha;
             };
             const { data: pr } = await github.rest.pulls.get({