UnitTest for TestListVolumeName() And TestUseProxy() And TestDetachVolume()

[zhengshiqiang47]

Ⅰ. Describe what this PR did

add UnitTest for TestListVolumeName() And TestUseProxy() And TestDetachVolume()

Ⅱ. Does this pull request fix one issue?

fixes #1760 #1761 #1763

Ⅲ. Describe how you did it

add unitTest

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

baiji group five

[CLAassistant]

All committers have signed the CLA.

[pouchrobot]

We found this is your first time to contribute to Pouch, @zhengshiqiang47
👏 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! 🍻

[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    #1785   +/-   ##
=========================================
  Coverage          ?   56.64%           
=========================================
  Files             ?      200           
  Lines             ?    15657           
  Branches          ?        0           
=========================================
  Hits              ?     8869           
  Misses            ?     5693           
  Partials          ?     1095

Flag	Coverage Δ
#critest	33.53% <ø> (?)
#integrationtest	37.56% <ø> (?)
#unittest	20.75% <ø> (?)

[pouchrobot]

@zhengshiqiang47 Thanks for your contribution. 🍻
Please sign off in each of your commits.