chore: fix illegal identifier in workflow (#19965)

Fixing this error:

```
The workflow is not valid. .github/workflows/close-stale-prs.yml (Line: 6, Col: 3): The identifier 'rix0rrr/close-stale-prs' is invalid. IDs may only contain alphanumeric characters, '_', and '-'. IDs must start with a letter or '_' and and must be less than 100 characters.
```

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: rix0rrr

.github/workflows/close-stale-prs.yml

@@ -3,7 +3,7 @@ on:
     # Cron format: min hr day month dow
     - cron: "0 0 * * *"
 jobs:
-  rix0rrr/close-stale-prs:
+  close-stale-prs:
     permissions:
       pull-requests: write
     runs-on: ubuntu-latest