fix: fix vue2 array reactive bug

[yiyunwan]

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What have you changed?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (d6f827c) 99.55% compared to head (5ce9a86) 99.55%.
Report is 1 commits behind head on formily_next.

Additional details and impacted files

@@              Coverage Diff              @@
##           formily_next    #4042   +/-   ##
=============================================
  Coverage         99.55%   99.55%           
=============================================
  Files               152      152           
  Lines              6717     6720    +3     
  Branches           1821     1822    +1     
=============================================
+ Hits               6687     6690    +3     
  Misses               30       30           

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