HHH-5843 Avoid useless branches during HQL parsing when trace logging is disabled

Many well-formatted and indented Strings were built up for each element of a parsed HQL string, for each tree node. The purpose was to feed invocations of <code>log.trace()</code>. The information was added to the log regardless of the log level. This caused extra output and larger log files. Hibernate now checks the log level, and only includes the formatted output when the log level is <literal>TRACE</literal>.