replacesearchbar: use html.parser in all BeautifulSoup calls

Avoid log spam:

/app/replacesearchbar.py:34: GuessedAtParserWarning: No parser was
explicitly specified, so I'm using the best available HTML parser for
this system ("lxml"). This usually isn't a problem, but if you run this
code on another system, or in a different virtual environment, it may
use a different parser and behave differently.

Bug: T362397

Edited by Filippo Giunchedi

Merge request reports

Loading