Handle branch token update with long poll API (#4943)

<!-- Describe what has changed in this PR -->
**What changed?**
Handle branch token update with long poll API

<!-- Tell your future self why have you made these changes -->
**Why?**
Simply compare branch token is not a good way to tell if the branch is
changed.

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test? Checked in staging env? -->
**How did you test it?**
release testing

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**Is hotfix candidate?**
Yes

common/serviceerror/current_branch_changed.go

@@ -42,6 +42,7 @@ type (
 )
 
 // NewCurrentBranchChanged returns new CurrentBranchChanged error.
+// TODO: Update CurrentBranchChanged with event id and event version. Do not use branch token bytes as branch identity.
 func NewCurrentBranchChanged(currentBranchToken, requestBranchToken []byte) error {
 	return &CurrentBranchChanged{
 		Message:            "Current branch token and request branch token doesn't match.",

proto/internal/temporal/server/api/historyservice/v1/request_response.proto

@@ -80,6 +80,7 @@ message GetMutableStateRequest {
     temporal.api.common.v1.WorkflowExecution execution = 2;
     int64 expected_next_event_id = 3;
     bytes current_branch_token = 4;
+    temporal.server.api.history.v1.VersionHistoryItem version_history_item = 5;
 }
 
 message GetMutableStateResponse {
@@ -115,6 +116,7 @@ message PollMutableStateRequest {
     temporal.api.common.v1.WorkflowExecution execution = 2;
     int64 expected_next_event_id = 3;
     bytes current_branch_token = 4;
+    temporal.server.api.history.v1.VersionHistoryItem version_history_item = 5;
 }
 
 message PollMutableStateResponse {

proto/internal/temporal/server/api/token/v1/message.proto

@@ -38,6 +38,7 @@ message HistoryContinuation {
     temporal.server.api.history.v1.TransientWorkflowTaskInfo transient_workflow_task = 7;
     bytes branch_token = 8;
     reserved 9;
+    temporal.server.api.history.v1.VersionHistoryItem version_history_item = 10;
 }
 
 message RawHistoryContinuation{