fix: support devServer: false

[alexander-akait]

What kind of change does this PR introduce?

feature #2947

Did you add tests for your changes?

WIP

If relevant, did you update the documentation?

WIP

Summary

WIP

Does this PR introduce a breaking change?

WIP

Other information

WIP

[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (09bfb16) 90.59% compared to head (c23286b) 68.90%.
Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #4045       +/-   ##
===========================================
- Coverage   90.59%   68.90%   -21.70%     
===========================================
  Files          22       21        -1     
  Lines        1702     1701        -1     
  Branches      491      491               
===========================================
- Hits         1542     1172      -370     
- Misses        160      529      +369     

Files	Coverage Δ
packages/webpack-cli/src/webpack-cli.ts	72.08% <ø> (-20.56%)	⬇️
packages/serve/src/index.ts	73.50% <40.00%> (-5.97%)	⬇️

... and 11 files with indirect coverage changes

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[alexander-akait]

@snitin315 We should allow false for devServer in webpack, feel free to send a PR

[snitin315]

Sure, I'll update in webpack