Adressing linter issues in netext, netext/httpext packages

[olegbespalov]

What?

This PR addresses the linter issues in the netext package.

It's better to do a review by commits. I've tried to combine them for the impact.

The first commit is applying simple changes.

Everything else deserves a more focused look since it also contains some refactorings.

Note: one linter issue is still there:

lib/netext/httpext/request.go:122:2                nestif             `if preq.Body != nil` has complex nested blocks (complexity: 6)

Since the function it deserves a separate PR, it's more complicated.

k6/lib/netext/httpext/request.go

Lines 109 to 114 in 856a767

	// MakeRequest makes http request for tor the provided ParsedHTTPRequest.
	//
	// TODO: split apart...
	//
	//nolint:cyclop, gocyclo, funlen, gocognit
	func MakeRequest(ctx context.Context, state *lib.State, preq *ParsedHTTPRequest) (*Response, error) {

Also, grpcext package's linter issues have yet to be touched since I'm planning to address them in #3152

Why?

As we agreed, we have to fix the linter issues presented in the master branch.

Checklist

• I have performed a self-review of my code.
• I have added tests for my changes.
• I have run linter locally (make lint) and all checks pass.
• I have run tests locally (make tests) and all tests pass.
• I have commented on my code, particularly in hard-to-understand areas.

Related PR(s)/Issue(s)

Part of #769

[codecov-commenter]

Codecov Report

Attention: 6 lines in your changes are missing coverage. Please review.

Comparison is base (e23ebec) 73.16% compared to head (c8ccf57) 73.18%.
Report is 1 commits behind head on master.

❗ Current head c8ccf57 differs from pull request most recent head 4970d55. Consider uploading reports for the commit 4970d55 to get more accurate results

Files	Patch %	Lines
lib/netext/httpext/compression.go	75.00%	5 Missing ⚠️
lib/netext/httpext/tracer.go	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3484      +/-   ##
==========================================
+ Coverage   73.16%   73.18%   +0.01%     
==========================================
  Files         267      267              
  Lines       20076    20076              
==========================================
+ Hits        14689    14692       +3     
+ Misses       4471     4470       -1     
+ Partials      916      914       -2     

Flag	Coverage Δ
ubuntu	73.13% <76.00%> (+0.01%)	⬆️
windows	73.04% <76.00%> (+0.01%)	⬆️

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[mstoykov]

LGTM, but instead of sparkling nolint:revive it is just better to replace the unused arguments name with _