Edit logger name in log4j2-test.xml files

Change the C to c in the pattern layout for all log4j2-test.xml files, this will allow us to have the logger name that published the logging event instead of the fully qualified class name of the caller issuing the logging request, which in case of a bridge (JCL to log4j2 for instance) will output the bridge class.

See https://logging.apache.org/log4j/2.x/manual/layouts.html#patterns