[10.x] Remove option from make:rule re-added by mistake

[rodrigopedra]

PR #44016 re-added the --invokable option to the MakeRuleCommand after it was removed by PR #43868

As Invokable rules will be the default in 10.x, this PR removes this option again.

[rodrigopedra]

By the way, would a PR allowing current/regular class rule creation be considered?

I have many rules where I use the translator within the message() method, and when having multiple "failure" points (think of early returns for multiple assessment), repeating the failure message + translation boilerplate when it has placeholders is cumbersome.

I think everyone will use the newer invokable design more, but I guess keeping the old-school style as an easy to create alternative presents no harm.

If this would be considered, I can send a PR.

EDIT: Reading the docs, I see translator has built-in support. Still the many early returns for multiple assessments stands.

As an example I have a custom rule to validate some allowed file formats like below, where to me seems simpler to keep the current style -- maybe I am biased by habit.

public function passes($attribute, $value): bool
{
    if ($this->validateMimes($attribute, $value, $this->extensions)) {
        return true;
    }

    if ($this->validateMimetypes($attribute, $value, $this->mimetypes->all())) {
        return true;
    }

    if ($this->isInvalidFile($value)) {
        return false;
    }

    if ($this->fileHasExpectedMimeType($value)) {
        return true;
    }

    if ($this->isOffice2007File($value)) {
        return true;
    }

    if ($this->isWindowsMediaAudioFile($value)) {
        return true;
    }

    if ($this->expectsTextFile() && $this->clientSaysFileIsTextFile($value)) {
        return ! $this->isBinaryFile($value);
    }

    return false;
}

public function message(): string
{
    return trans('invalid.file', ['extensions' => \implode(', .', $this->extensions)]);
}

For context: most if checks were added after particular valid files -- sent by users -- failed previous checks. This is why some might seem redundant.

[rodrigopedra]

Don´t know why tests are failing. This PR just removes a line for an unused command option.