XRENDERING-621: Make rendering errors translatables and extendables

* remove test leftovers

xwiki-rendering-transformations/xwiki-rendering-transformation-macro/src/main/resources/ApplicationResources.properties

@@ -42,8 +42,8 @@
 #     old.key.name=Some translation
 ###############################################################################
 
-rendering.macro.error.unknown=Unknown macro2: {0}.
-rendering.macro.error.unknown.description=The2 [{0}] macro is not in the list of registered macros. Verify the spelling or contact your administrator.
+rendering.macro.error.unknown=Unknown macro: {0}.
+rendering.macro.error.unknown.description=The [{0}] macro is not in the list of registered macros. Verify the spelling or contact your administrator.
 rendering.macro.error.failed=Failed to execute the [{0}] macro.
 rendering.macro.error.invalid=Invalid macro: {0}.
 rendering.macro.error.standalone=The [{0}] macro is a standalone macro and it cannot be used inline.