Unmute IndexStatsIT#testThrottleStats

The test was fixed and unmuted in elastic#126113, but then muted back by mistake in elastic#126193

Author: arteam

muted-tests.yml

@@ -315,9 +315,6 @@ tests:
 - class: org.elasticsearch.xpack.test.rest.XPackRestIT
   method: test {p0=ml/start_data_frame_analytics/Test start given dest index is not empty}
   issue: https://github.com/elastic/elasticsearch/issues/125909
-- class: org.elasticsearch.indices.stats.IndexStatsIT
-  method: testThrottleStats
-  issue: https://github.com/elastic/elasticsearch/issues/125910
 - class: org.elasticsearch.xpack.test.rest.XPackRestIT
   method: test {p0=transform/transforms_stats/Test get transform stats with timeout}
   issue: https://github.com/elastic/elasticsearch/issues/125975