bitbake: lib: remove unused imports

removed unused imports which made the code harder to read, and slightly
but less efficient

(Bitbake rev: 4367692a932ac135c5aa4f9f2a4e4f0150f76697)

Signed-off-by: Frazer Clews <frazer.clews@codethink.co.uk>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bs4/builder/_html5lib.py

@@ -2,7 +2,6 @@ __all__ = [
     'HTML5TreeBuilder',
     ]
 
-from pdb import set_trace
 import warnings
 from bs4.builder import (
     PERMISSIVE,