[6.x] Split specifyParameter() to external trait

[crynobone]

While building orchestra/canvas, I found out that while it would be nice
to use Illuminate\Console\Command the requirements to have Laravel (or
at least the Container) configure make it slightly harder to build PHP
CLI code based on symfony console with a little Laravel flavour.

    /**
     * Configure the command options.
     *
     * @return void
     */
    protected function configure()
    {
        $this->ignoreValidationErrors();

        $this->setName($this->name)
                ->setDescription($this->description)
                ->addArgument('name', InputArgument::REQUIRED, "The name of the {$this->fileType}");

        $this->specifyParameters();
    }

Signed-off-by: Mior Muhammad Zaki crynobone@gmail.com

[GrahamCampbell]

The trait needs to have getDefinition, addArgument and addOption as abstract methods.

[crynobone]

addArgument and addOption both will have scalar type-hint in 5.0. Does Laravel want to have this?

[GrahamCampbell]

Laravel 6 requires Symfony console 4, so no typehints needed. For Laravel 7, yes, we'll need to match the symfony method signature, since that needs Symfony console 5.

[GrahamCampbell]

The same as some of Laravel's internals has typehints to match phpunit's stuff.