DidSetKeyMetadata returns incorrect response

[bootstrapsp]

Describe the bug
rpc DidSetKeyMetadata (DidSetKeyMetadataRequest) returns (DidSetKeyMetadataRequest) {} should return DidSetKeyMetadataResponse instead of DidSetKeyMetadataRequest.

DidSetKeyMetadataResponse defines the ErrorCode which should be returned as an outcome of setting the KeyMetaData

DidSetKeyMetadataResponse is defined in the proto however not used.

To Reproduce
No steps to reproduce. This is just incorrect definition of RPC method

Expected behavior
Should return DidSetKeyMetadataResponse containing appropriate error code.