[FIX] lcc_members: missing dependency to membership_extension

[jojolb]

Issue when:

• starting an environment from scratch using odoo image docker.0k.io/mirror/odoo:rc_12.0-MYC-INIT-3.7
• trying to install module lcc_members

Module fails to install because of a missing field:

Field `category_id` does not exist

Error context:
View `membership_line.view.form`
[view_id: 1094, xml_id: n/a, model: membership.membership_line, parent_id: n/a]
None" while parsing /opt/odoo/auto/lokavaluto/lcc_members/views/membership_lines.xml:19, near

This field is added to the model membership_line by the OCA addon membership_extension

Adding this addon to dependencies list fixes the issue.

[jojolb]

Already fixed in another PR