[ISSUE #139]add locker for updating data

[wolftankk]

What is the purpose of the change

• Add locker in offset_store's update and persist

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (native@5e093c8). Click here to learn what that means.
The diff coverage is 0%.

@@            Coverage Diff            @@
##             native     #146   +/-   ##
=========================================
  Coverage          ?   14.35%           
=========================================
  Files             ?       42           
  Lines             ?     4181           
  Branches          ?        0           
=========================================
  Hits              ?      600           
  Misses            ?     3488           
  Partials          ?       93

Impacted Files	Coverage Δ
consumer/offset_store.go	1.57% <0%> (ø)

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[wenfengwang]

LGTM