[REF] link_tracker: reorganize python according to guidelines
[REF] link_tracker: reorganize python according to guidelines

This was not correctly done when splitting the module at fd5361c0f7116e951cf9e69e2d97a8ccb07ce1b6.
Future commits will clean a bit the code in order to better understand how
this module works.

This commit is linked to task ID 1896681 and PR #27975. No functional change
should occur with this commit as it contains only renaming / move.
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo