[AN] feat: 모임 수정 기능 구현

[jinuemong]

이슈

• close #434

개발 사항

• 모임 수정 기능 완성🔥

[github-actions[bot]]

Test Results

3 tests  ±0   3 :white_check_mark: ±0   0s :stopwatch: ±0s 1 suites ±0   0 :zzz: ±0  1 files   ±0   0 :x: ±0 

Results for commit f1e2df06. ± Comparison against base commit edbd72f2.