[BUGFIX] Use reflection information in getGettablePropertyNames

In \TYPO3\CMS\Extbase\Reflection\ObjectAccess there is a method to get
all available property names of an object. Currently all get/is/has
methods are joined as they can be fetch from Extbase as well. But for
those methods it is necessary to respect their arguments as Extbase
calls those functions without any argument. This can trigger PHP warnings.

The patch uses a class reflection to get public properties and inspect
the method arguments. Only those functions without arguments or only
optional arguments are considered as valid property name.

Resolves: #78270
Releases: master, 7.6
Change-Id: Ie286dca2a249b73d3dc58f7388dda593a678db3d
Reviewed-on: https://review.typo3.org/50197


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Philipp Gampe <philipp.gampe@typo3.org>
Tested-by: Philipp Gampe <philipp.gampe@typo3.org>