Fix external dependency

[JJ]

By putting it in here. Closes #640.

[tbrowder]

Looks good to me. Thanks, @JJ!

[vrurg]

Actually, considering https://github.com/Raku/roast/blob/master/packages/Test-Helpers/lib/Test/Util.pm6#L107 – what's the point? I highly recommend reverting this PR and re-implementing it with the standard routine.

[JJ]

OK, I'll do it adding to the other one, instead of reverting this commit.

[JJ]

The problem is that the signature is not exactly the same, not to mention the name:

Cannot resolve caller is_run(Str:D, Str:D, :compiler-args(Array), :exitcode(Int), :out(Str)); none of these signatures match:
    (Str $code, %expected, *%o)
    (Str $code, Str $input, %expected, *%o)
    (Str $code, %expected, Str $name, *%o)
    (Str $code, Str $input, %expected, Str $name, *%o)
  in block  at S26-documentation/block-leading-user-format.t line 56
  in block <unit> at S26-documentation/block-leading-user-format.t line 50

I can try and adapt the call to one of these signatures, or move the routine to that file. I'll see what can be done.

[JJ]

Also, is-run uses standard run while lexically Test::Utils' got its own run. So moving it there does not really work either. I don't think it's worth the while to reverse it, or even to move this is-run to Test::Helpers, but I'd be happy to hear other opinions.

[vrurg]

I have committed a fix which makes use of roast is_run. The differences are rather subtle as except for different signature I never had a problem with is_run.