Support run tests which have complex shell commands

[mozillazg]

There are some scored item have been marked manual because of it need complex shell commands to run test but kube-bench don't support it. Change to support run complex shell commands can avoid this issue and fix issues like #598 too.

kube-bench run tests via parse test command as a simple single line command then run it, this way don't support complex shell commands.

kube-bench/check/check.go

Line 206 in 7cd6b32

func textToCommand(s string) []*exec.Cmd {

What about change to run the test command just as run a shell script, this way can support complex commands.