This reverts commit d6b854306c.
The reverted commit introduced issues in patching class methods.
Introducing getters in the patch function is not actually compatible
with the original method patching.
Test for patch method is also introduced to guard patch from future
invalid modification that happened.
A more robust way of patching classes is now being developed.
closesodoo/odoo#47557
Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>