Fix data stream stats YAML test

Occasional shard allocation issues were causing the YAML tests to fail
because the shard that had the document with the max timestamp in it
would be unavailable.

Author: nielsbauman

modules/data-streams/src/yamlRestTest/resources/rest-api-spec/test/data_stream/120_data_streams_stats.yml

@@ -185,8 +185,18 @@ setup:
         body:  { "@timestamp": 1593639468350 }
         refresh: true
 
+  # Wait for the shards to be allocated to avoid missing results in the stats request
+  - do:
+      cluster.health:
+        index: simple-data-stream1,simple-data-stream2
+        wait_for_status: green
+        wait_for_no_relocating_shards: true
+
   - do:
       indices.data_streams_stats: {}
+  - match: { _shards.total: 3 }
+  - match: { _shards.successful: 3 }
+  - match: { _shards.failed: 0 }
   - match: { data_stream_count: 2 }
   - match: { backing_indices: 3 }
   - length: { data_streams: 2 }

muted-tests.yml

@@ -102,9 +102,6 @@ tests:
 - class: org.elasticsearch.packaging.test.ArchiveTests
   method: test51AutoConfigurationWithPasswordProtectedKeystore
   issue: https://github.com/elastic/elasticsearch/issues/118212
-- class: org.elasticsearch.datastreams.DataStreamsClientYamlTestSuiteIT
-  method: test {p0=data_stream/120_data_streams_stats/Multiple data stream}
-  issue: https://github.com/elastic/elasticsearch/issues/118217
 - class: org.elasticsearch.xpack.ccr.rest.ShardChangesRestIT
   method: testShardChangesNoOperation
   issue: https://github.com/elastic/elasticsearch/issues/118800