Fix get user in group members nil panic

[a3d21]

修复GetUserInGroupMembers nil panic

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[codecov]

Codecov Report

Merging #1324 (97fc0e3) into main (d2f0af1) will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##            main   #1324   +/-   ##
=====================================
  Coverage   2.44%   2.44%           
=====================================
  Files         13      13           
  Lines        778     778           
=====================================
  Hits          19      19           
  Misses       756     756           
  Partials       3       3