New constructor for AWSSchemaRegistryClient request

[MrAnnix]

Currently, three constructors are provided for the com.amazonaws.services.schemaregistry.common.AWSSchemaRegistryClient class. One of them, AWSSchemaRegistryClient(@NonNull GlueClient glueClient) only receives the glue client and the GlueSchemaRegistryConfiguration glueSchemaRegistryConfiguration attribute remains uninitialized.

This causes most methods that query the Glue Schema Registry to fail by throwing a NullPointerException.

I think it would be interesting to replace, or at least, add another constructor that also instantiates the GlueSchemaRegistryConfiguration glueSchemaRegistryConfiguration attribute.