BUGFIX: 4909 fusion plugins and tests

[mhsdesign]

Resolves: #4909

Based on #5305 introduces a step to declare a flow controller in behat:

When I declare the following controller 'Vendor\Site\Controller\MyPluginWithFusionController':
"""php
<?php
namespace Vendor\Site\Controller;

use Neos\Flow\Mvc\Controller\ActionController;

class MyPluginWithFusionController extends ActionController
{
    public function renderAction()
    {
    }
}
"""

This comes with good and bad things.
The good thing is that the test is self contained and i have seen behat for example see also use that they create virtual php to test if the frame-work works.
Now the downside is that because of php there can only be ONE MyPluginWithFusionController across all tests declared which are executed in the same run. But for now this is not a problem as there are only two such fakes.
Another problem is that we need some hacks (see BehatRuntimeActionController) to actually make this work.

At first i attempted to have the files also separated in another location in (Test/Functional) of Neos.Neos but aside from them being spread around the whole planed i had problems with the proxybuilding there too.

But i believe that we do want to use behat to write self contained tests even if its hard right now but flow has to adjust at some point to this needs hopefully ^^.

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• Code follows the PSR-2 coding style
• Tests have been created, run and adjusted as needed
• The PR is created against the lowest maintained branch
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[kitsunet]

I don't like the PHP in the behat but I don't think it warrants blocking stuff. We can refactor the tests any time.

[mficzel]

Generally fine by 👀 ... would remove the magic renaming of the ActionController class and use the real name.