Unmute test that was fixed long ago (#124695)

The test was fixed in in d48cf3f

Author: nicktindall

muted-tests.yml

@@ -272,9 +272,6 @@ tests:
 - class: org.elasticsearch.xpack.esql.heap_attack.HeapAttackIT
   method: testEnrichExplosionManyMatches
   issue: https://github.com/elastic/elasticsearch/issues/122913
-- class: org.elasticsearch.repositories.gcs.GoogleCloudStorageServiceTests
-  method: testClientsAreNotSharedAcrossRepositories
-  issue: https://github.com/elastic/elasticsearch/issues/123090
 - class: org.elasticsearch.smoketest.DocsClientYamlTestSuiteIT
   method: test {yaml=reference/troubleshooting/common-issues/disk-usage-exceeded/line_65}
   issue: https://github.com/elastic/elasticsearch/issues/123094