feat: add method for revoking public key

Add it to the `.proto` definition of the auth service.

Signed-off-by: Artem Chernyshev <artem.chernyshev@talos-systems.com>

Author: Unix4ever

api/auth/auth.pb.go

@@ -38,8 +38,13 @@ message ConfirmPublicKeyRequest {
   string public_key_id = 1;
 }
 
+message RevokePublicKeyRequest {
+  string public_key_id = 1;
+}
+
 service AuthService {
   rpc RegisterPublicKey(RegisterPublicKeyRequest) returns (RegisterPublicKeyResponse);
   rpc AwaitPublicKeyConfirmation(AwaitPublicKeyConfirmationRequest) returns (google.protobuf.Empty);
   rpc ConfirmPublicKey(ConfirmPublicKeyRequest) returns (google.protobuf.Empty);
+  rpc RevokePublicKey(RevokePublicKeyRequest) returns (google.protobuf.Empty);
 }