chore: add keep label to mark issues/prs from being marked as stale

- [x] added keep label to repo
- [x] add `exempt-issue-labels` and `exempt-pre-labels` to stale config

Signed-off-by: jmeridth <jmeridth@gmail.com>

Author: jmeridth

.github/workflows/stale.yml

@@ -23,3 +23,5 @@ jobs:
             This pull request has been automatically marked as stale because it has not
             had recent activity. It will be closed if no further activity occurs.
             Thank you for your contributions.
+          exempt-issue-labels: keep
+          exempt-pr-labels: keep