opened
jiyingtk
username_0
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### What problem does this PR solve? <!--add the issue link with summary if it exists-->
Region flow statistics would be inaccurate when transfer leader occurs.

### What is changed and how it works?
Use time interval reported from region heartbeat to calculate flow.

### Check List <!--REMOVE the items that are not applicable-->

Tests <!-- At least one of them must be included. -->

 - Manual test
statistics: fix region flow calculation
issue