Refactor CaseInsensitiveMap on ShardingSphereMetaData.databases #10586

Job	Run time
Import Global Environment / init-environment	4s
Build E2E Image	8m 35s
E2E - Agent with MySQL (proxy, tracing, jaeger)	6m 43s
E2E - Agent with MySQL (proxy, tracing, zipkin)	6m 41s
E2E - Agent with MySQL (proxy, metrics, prometheus)	7m 1s
E2E - Agent with MySQL (proxy, logging, file)	6m 40s
E2E - Agent with MySQL (jdbc, logging, file)	6m 41s
E2E - Agent with MySQL (jdbc, metrics, prometheus)	8m 20s
E2E - Agent with MySQL (jdbc, tracing, jaeger)	7m 8s
E2E - Agent with MySQL (jdbc, tracing, zipkin)	6m 39s
	1h 4m 32s

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