Don't call base class version unnecessarily in wxLogWindow::DoLogTextAtLevel().

Don't call base class version unnecessarily in wxLogWindow::DoLogTextAtLevel().

This is unnecessary as the log message is already passed to the previous
logger by the base class wxLogChain::DoLogRecord() implementation. Worse, it's
actively harmful as it resulted in asserts in wxLog::DoLogText() when built
with WXWIN_COMPATIBILITY_2_8==0.

Closes #11526.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@63167 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775