[REM] core: support for werkzeug interactive debugger

With the special support for postmortem debugging removed, the
likelihood of needing / wanting the werkzeug remote debugger seems
even more remote (as it works in strictly less situations, only for
frontend non-json requests).

So remove that as well.

closes odoo/odoo#115076

Signed-off-by: Xavier Morel (xmo) <xmo@odoo.com>