XWIKI-10247: Impossible to use a rendering syntax installed as extension
* fix test

(cherry picked from commit 0d2af177b55b3187a75663b886cb062d8a47ff3f)

Conflicts:
	xwiki-platform-core/xwiki-platform-rendering/xwiki-platform-rendering-xwiki/src/test/java/org/xwiki/rendering/internal/parser/DefaultContentParserTest.java