fix: using new dev server API for v4

[alexander-akait]

What kind of change does this PR introduce?

bugfix

Did you add tests for your changes?

existing

If relevant, did you update the documentation?

No need

Summary

due webpack/webpack-dev-server#3608

Does this PR introduce a breaking change?

No

Other information

No

[codecov]

Codecov Report

Merging #2886 (9642c17) into master (1a337aa) will decrease coverage by 0.10%.
The diff coverage is 62.50%.

@@            Coverage Diff             @@
##           master    #2886      +/-   ##
==========================================
- Coverage   94.95%   94.84%   -0.11%     
==========================================
  Files          31       31              
  Lines        1704     1708       +4     
  Branches      484      486       +2     
==========================================
+ Hits         1618     1620       +2     
- Misses         86       88       +2     

Impacted Files	Coverage Δ
packages/serve/src/index.ts	83.53% <62.50%> (-0.84%)	⬇️

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