unmute test (#122939)

Backports the following commits to 8.17:  -
StressSearchServiceReaperIT_unmute_test (#122793)

Author: drempapis

muted-tests.yml

@@ -279,9 +279,6 @@ tests:
 - class: org.elasticsearch.xpack.spatial.search.GeoGridAggAndQueryConsistencyIT
   method: testGeoShapeGeoTile
   issue: https://github.com/elastic/elasticsearch/issues/115717
-- class: org.elasticsearch.search.StressSearchServiceReaperIT
-  method: testStressReaper
-  issue: https://github.com/elastic/elasticsearch/issues/115816
 - class: org.elasticsearch.xpack.spatial.search.GeoGridAggAndQueryConsistencyIT
   method: testGeoShapeGeoHex
   issue: https://github.com/elastic/elasticsearch/issues/115705