Mute testSynthesizeArrayRandomIgnoresMalformed (#125320)

Muting because of random failures on main branch.

muted-tests.yml

@@ -399,6 +399,9 @@ tests:
 - class: org.elasticsearch.reservedstate.service.ReservedClusterStateServiceTests
   method: testProcessMultipleChunks
   issue: https://github.com/elastic/elasticsearch/issues/125305
+- class: org.elasticsearch.index.mapper.NativeArrayIntegrationTestCase
+  method: testSynthesizeArrayRandomIgnoresMalformed
+  issue: https://github.com/elastic/elasticsearch/issues/125319
 
 # Examples:
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