Remove `DebugClear` method from ate-apiserver

[juli4n]

The DebugClear method in ate-apiserver deletes all data from ValKey. This has been useful in very early stages of the project where we change the data schema almost on a daily basis. As the schema gets more stable, we should remove this method, at least from the Control service.

substrate/pkg/proto/ateapipb/ateapi.proto

Line 67 in c1ab095

rpc DebugClear(DebugClearRequest) returns (DebugClearResponse) {}

[troychiu]

Hi Zoe Zhao (@zoez7) I can help with this.