add test for GetConflictConfigurations

[zhyzhyzhy]

Ⅰ. Describe what this PR did

add unit-test for getConflictConfigurations

Ⅱ. Does this pull request fix one issue?

fixed issue #1759

Ⅲ. Describe how you did it

create tests for target methods

Ⅳ. Describe how to verify it

go test and everything pass

Ⅴ. Special notes for reviews

baiji group 5

[pouchrobot]

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

[pouchrobot]

We found this is your first time to contribute to Pouch, @zhyzhyzhy
👏 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! 🍻

[pouchrobot]

ping @zhyzhyzhy
Conflict happens after merging a previous commit.
Please rebase the branch against master and push it back again. Thanks a lot.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@afc7a21). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #1872   +/-   ##
=========================================
  Coverage          ?   56.52%           
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  Files             ?      200           
  Lines             ?    15659           
  Branches          ?        0           
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  Hits              ?     8851           
  Misses            ?     5715           
  Partials          ?     1093

Flag	Coverage Δ
#critest	33.54% <ø> (?)
#integrationtest	37.65% <ø> (?)
#unittest	20.68% <ø> (?)