[REM] remove migration script from net_weight to weight

[legalsylvain]

the previous migration script was based on bad interpretation of the new unique weight field.

see OCA/product-attribute#894 for the whole discussion.

CC : @mbcosta, @pedrobaeza

[mbcosta]

Hi @legalsylvain
I think should be better keep the script and just change the field, instead weight_net use weight.

[legalsylvain]

hi @mbcosta not sure to understand.
In v8 : weight and weight_net
in V9 : weight

due to a bad documentation, I thought that the weight field in V9 was the old weight_net in V8, but if it's not the case, there is nothing to do in my opinion.
if not agree, could you explain which request to write ?

thanks !

[mbcosta]

you right, good work