feat: show '--node-env' in minimum help output

[snitin315]

What kind of change does this PR introduce?
feature

Did you add tests for your changes?
already present.

If relevant, did you update the documentation?
Yes
Summary
Show --node-env in minimum help output as it is custom flag provided by CLI. --help=verbose lists too many options not easy to find --node-env between them.

Does this PR introduce a breaking change?
No

Other information
No

[codecov]

Codecov Report

Merging #2411 (59af519) into master (78e2fa7) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2411   +/-   ##
=======================================
  Coverage   71.79%   71.79%           
=======================================
  Files          46       46           
  Lines        2177     2177           
  Branches      574      574           
=======================================
  Hits         1563     1563           
  Misses        614      614           

Impacted Files	Coverage Δ
packages/webpack-cli/lib/webpack-cli.js	91.92% <ø> (ø)

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[alexander-akait]

@snitin315 Can you rebase?

[anshumanv]

we can assert on it in help output test

[alexander-akait]

I think we need to use snapshots for help and output, it will allow us to see all the changes.

[anshumanv]

yep snapshot is better