修复创建mongodb原生连接时的错误 (hhyo#1291)

[weideguo]

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[request-info]

你好!感谢你反馈的问题/bug，但是你的描述好像是空的，我们需要你完整的信息，这样才能帮你解决问题 如果不知道怎么写，在新建issue的时候有若干个模板可供选择，祝好！

[codecov]

Codecov Report

Merging #1294 (70bf9b6) into master (e5e777b) will increase coverage by 0.00%.
The diff coverage is 75.00%.

@@           Coverage Diff           @@
##           master    #1294   +/-   ##
=======================================
  Coverage   77.90%   77.90%           
=======================================
  Files          77       77           
  Lines       12045    12046    +1     
=======================================
+ Hits         9384     9385    +1     
  Misses       2661     2661           

Impacted Files	Coverage Δ
sql/engines/mongo.py	48.37% <75.00%> (+0.08%)	⬆️

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