[FIX] tests: avoid traceback when websocket-client is not installed
[FIX] tests: avoid traceback when websocket-client is not installed

The account module needs to import Form from "tests.common" causing a
traceback when websocket-client module is not installed.

As this module is only required for the tests, there is no reason to add
it to the "requirements.txt" file.

With this commit, Odoo account can be installed even when
websocket-client is not installed, in that case, the HttpCase tests that
needs to run Chrome headless will be skipped with a warning.

Closes: #26404 
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo