Add autoclean to package-manager

[xuchaoying]

• Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

feat

• What is the related issue? (Use #issue_id to relate an open issue)

• Does this PR introduce a breaking change?

no

• Other information:

[codecov]

Codecov Report

Merging #159 into master will increase coverage by 1.83%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master    #159      +/-   ##
=========================================
+ Coverage   93.86%   95.7%   +1.83%     
=========================================
  Files          12      49      +37     
  Lines         326    1675    +1349     
=========================================
+ Hits          306    1603    +1297     
- Misses         20      72      +52

Impacted Files	Coverage Δ
...s/svrx-util/lib/package-manager/package-manager.js	97.4% <100%> (+0.19%)	⬆️
packages/svrx/lib/io/index.js	100% <0%> (ø)
packages/svrx/index.js	100% <0%> (ø)
packages/svrx/lib/plugin/svrx-plugin-open/index.js	87.5% <0%> (ø)
packages/svrx/lib/plugin/svrx-plugin-cors/index.js	85.71% <0%> (ø)
packages/svrx/lib/shared/cache.js	100% <0%> (ø)
packages/svrx/lib/plugin/system.js	90.82% <0%> (ø)
packages/svrx/lib/config-list.js	100% <0%> (ø)
...es/svrx/lib/plugin/svrx-plugin-livereload/index.js	28.57% <0%> (ø)
packages/svrx/lib/configure/builtinOption.js	100% <0%> (ø)
... and 28 more

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