add client identity to update-metadata request (#600)

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<!-- Describe what has changed in this PR -->
add client identity to update-metadata request

<!-- Tell your future self why have you made these changes -->
on the server side we generate a uuid identity. would be nice to allow
user to specify it instead

<!-- Are there any breaking changes on binary or code level? -->
**Breaking changes**


<!-- If this breaks the Server, please provide the Server PR to merge
right after this PR was merged. -->
**Server PR**

Author: carlydf

openapi/openapiv2.json

@@ -8275,6 +8275,10 @@
             "type": "string"
           },
           "description": "List of keys to remove from the metadata."
+        },
+        "identity": {
+          "type": "string",
+          "description": "Optional. The identity of the client who initiated this request."
         }
       },
       "description": "Used to update the user-defined metadata of a Worker Deployment Version."

openapi/openapiv3.yaml

@@ -11968,6 +11968,9 @@ components:
           items:
             type: string
           description: List of keys to remove from the metadata.
+        identity:
+          type: string
+          description: Optional. The identity of the client who initiated this request.
       description: Used to update the user-defined metadata of a Worker Deployment Version.
     UpdateWorkerDeploymentVersionMetadataResponse:
       type: object

temporal/api/workflowservice/v1/request_response.proto

@@ -2229,6 +2229,8 @@ message UpdateWorkerDeploymentVersionMetadataRequest {
     map<string, temporal.api.common.v1.Payload> upsert_entries = 3;
     // List of keys to remove from the metadata.
     repeated string remove_entries = 4;
+    // Optional. The identity of the client who initiated this request.
+    string identity = 6;
 }
 
 message UpdateWorkerDeploymentVersionMetadataResponse {