Query cache is not cleaned up in case of an index creation failure

[astefan]

Creating an index with index.mapper.dynamic setting will fail in 7.x with something like

java.lang.IllegalArgumentException: Setting index.mapper.dynamic was removed after version 6.0.0
	at org.elasticsearch.index.mapper.MapperService.<init>(MapperService.java:165) ~[elasticsearch-7.4.0.jar:7.4.0]
	at org.elasticsearch.index.IndexService.<init>(IndexService.java:180) ~[elasticsearch-7.4.0.jar:7.4.0]
	at org.elasticsearch.index.IndexModule.newIndexService(IndexModule.java:411) ~[elasticsearch-7.4.0.jar:7.4.0]
	at org.elasticsearch.indices.IndicesService.createIndexService(IndicesService.java:550) ~[elasticsearch-7.4.0.jar:7.4.0]
	at org.elasticsearch.indices.IndicesService.createIndex(IndicesService.java:499) ~[elasticsearch-7.4.0.jar:7.4.0]

But this seems to introduce a leak by creating the query cache before the index is created, and not cleaning the cache in case of failure. This manifests itself as OptOutQueryCache instances kept alive in heap, each of them referencing the non-existent, attempted-to-be-created-and-failed indexName.

[elasticmachine]

Pinging @elastic/es-distributed (:Distributed/CRUD)