Update stale.yml to use old version as a bug fix (#19532)

### Description
Changed the actions/stale version back to v8 from v9.



### Motivation and Context
There is a well-documented issue w/ the new actions/stale version
(v9.0.0) that causes the following error: "Error delete _state: [403]
Resource not accessible by integration". See
actions/stale#1133 for more context.

This issue is preventing the stale bot from labeling stale issues since
the version was updated b/c the action can no longer access the cache
and cannot apply labels to all issues due to GH API rate limiting.

There are two potential fixes if we continue to use the new version: (1)
run the action on all PRs/issues to avoid using the cache or (2) give
write access to the endpoints listed in
https://docs.github.com/en/rest/authentication/permissions-required-for-fine-grained-personal-access-tokens?apiVersion=2022-11-28#repository-permissions-for-actions.
Neither of these options is preferable, so I am going to wait until the
bug is fixed.

Note: The old version (v8.0.0) uses Node 16, which will be deprecated in
Spring 2024, instead of Node 20, so we should keep an eye on [this
issue](actions/stale#1133) to see when they
make the fix and we can switch back to the new version.

Author: sophies927

.github/workflows/stale.yml

@@ -13,7 +13,7 @@ jobs:
       issues: write
       pull-requests: write
     steps:
-      - uses: actions/stale@v9.0.0
+      - uses: actions/stale@v8
         with:
           # Comma separated list of labels that can be assigned to issues to exclude them from being marked as stale
           exempt-issue-labels: contributions welcome, feature request, regression