[FIX] base: handle error when editing comment in view's architecture

Currently, When the user is adding a double hyphen or space or anything within a
comment in a view's architecture and tries to save the view, then an error
occurs.

To reproduce the issue:
1. Go to Settings > Technical > Views > open a view.
2. In View Architecture comment out a line.
3. Add a double hyphen or space or anything within the comment.
4. Then save manually, the error will occur.

To solve this issue the error has been handled using a try-except block in
'parse_html' method.

sentry-4306359331

closes odoo/odoo#129969

Signed-off-by: Nicolas Lempereur (nle) <nle@odoo.com>