[cleanup] Math/rand.Seed deprecated

[n4x2]

Summary

Since Go 1.20 release, math/rand.Seed is marked "Deprecated"

Looks like five instances to consider updating:

find . -name "*.go" -type f -print | xargs grep .Seed

./pkg/pwgen/pwgen_test.go:      mrand.Seed(1789)
./pkg/pwgen/rand.go:    rand.Seed(time.Now().Unix() + int64(os.Getpid()+os.Getppid()))
./pkg/fsutil/fsutil.go: rand.Seed(time.Now().UnixNano())
./pkg/gitconfig/config_test.go: rand.Seed(time.Now().Unix())
./internal/action/binary_test.go:       rand.Seed(42)

[dominikschulz]

Usually "Deprecated" just means it's finally stable ;)

But I'll check what the recommendation is these days.

[dominikschulz]

• pkg/pwgen/rand.go This one can Go away once we don't need to support Go 1.20 anymore.
• pkg/fsutil/fsutil.go Same here.

For the test files we actually rely on detemernistic output, so we will need some more changes. We need to introduce a global variable with a local generator and seed it like this New(NewSource(seed)). See https://pkg.go.dev/math/rand#Seed

[orangekame3]

@dominikschulz
Hi, I'd like to take on this issue if that's okay.

[dominikschulz]

@orangekame3 Feel free to do so

[orangekame3]

@dominikschulz
Thank you. I've created a PR. Please check it out:
#2675