fix issue #1759 baiji-group 264-2

[panzaiyu]

Ⅰ. Describe what this PR did

Add unit-test for getConflictConfigurations method

Ⅱ. Does this pull request fix one issue?

fixes #1759

Ⅲ. Describe how you did it

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[pouchrobot]

@panzaiyu Thanks for your contribution. 🍻
Please sign off in each of your commits.

[pouchrobot]

We found this is your first time to contribute to Pouch, @panzaiyu
👏 We really appreciate it.
Just remind that you have read the contribution guide: https://github.com/alibaba/pouch/blob/master/CONTRIBUTING.md
If you didn't, you should do that first. If done, welcome again and please enjoy hacking! 🍻

[CLAassistant]

All committers have signed the CLA.

[codecov-io]

Codecov Report

Merging #1801 into master will increase coverage by 0.15%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1801      +/-   ##
==========================================
+ Coverage    56.3%   56.46%   +0.15%     
==========================================
  Files         200      200              
  Lines       15657    15657              
==========================================
+ Hits         8816     8841      +25     
+ Misses       5745     5724      -21     
+ Partials     1096     1092       -4

Flag	Coverage Δ
#critest	33.52% <ø> (+0.04%)	⬆️
#integrationtest	37.7% <ø> (+0.04%)	⬆️
#unittest	20.41% <ø> (+0.08%)	⬆️

Impacted Files	Coverage Δ
cri/v1alpha2/cri.go	66.13% <0%> (+0.17%)	⬆️
daemon/mgr/container.go	53.46% <0%> (+0.31%)	⬆️
ctrd/container.go	50.17% <0%> (+1.37%)	⬆️
ctrd/image.go	79.2% <0%> (+2.47%)	⬆️
daemon/config/config.go	35.8% <0%> (+13.58%)	⬆️