Refactor AppendError to use strings.Contains

[alexandear]

The PR replaces regexp.MustCompile with strings.Contains to simplify and performance.

These simple benchmark show, that version with strings.Contains is more performant.

Benchmark

func BenchmarkAppendError(b *testing.B) {
	analyzer := gosec.NewAnalyzer(nil, false, false, false, 1, nil)

	file := "test.go"
	err := errors.New("test error")

	for i := 0; i < b.N; i++ {
		analyzer.AppendError(file, err)
	}
}

Before (regexp.MustCompile):

-test.shuffle 1734344546323474000
goos: darwin
goarch: arm64
pkg: github.com/securego/gosec/v2
cpu: Apple M1 Pro
BenchmarkAppendError
BenchmarkAppendError-8   	   33993	     35043 ns/op	    3927 B/op	      23 allocs/op
PASS
coverage: 3.7% of statements
ok  	github.com/securego/gosec/v2	3.471s

After (strings.Contains):

Running tool: /opt/homebrew/bin/go test -benchmem -run=^$ -coverprofile=/var/folders/pk/5dzf3qsj6l18s2b3zfw194840000gn/T/vscode-goN80OyX/go-code-cover -bench ^BenchmarkAppendError$ github.com/securego/gosec/v2 -v -race -shuffle=on -parallel=8 -failfast

-test.shuffle 1734344511315519000
goos: darwin
goarch: arm64
pkg: github.com/securego/gosec/v2
cpu: Apple M1 Pro
BenchmarkAppendError
BenchmarkAppendError-8   	 1341718	       874.3 ns/op	     160 B/op	       0 allocs/op
PASS
coverage: 3.6% of statements
ok  	github.com/securego/gosec/v2	4.038s

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 66.65%. Comparing base (1216c9b) to head (7215ab2).
Report is 23 commits behind head on master.

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1270      +/-   ##
==========================================
- Coverage   68.49%   66.65%   -1.85%     
==========================================
  Files          75       75              
  Lines        4384     5185     +801     
==========================================
+ Hits         3003     3456     +453     
- Misses       1233     1581     +348     
  Partials      148      148              

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[ccoVeille]

The test is indeed faster

But checking the error message still looks dirty

Is there a case where this could not be used ?

https://pkg.go.dev/go/build#NoGoError

[ccoVeille]

@alexandear ?

[alexandear]

Thanks. Created #1273