[FIX] crm: display right partner and action when converting lead

Issue
	- Create a partner with email 'aaa@test.com'
	- In CRM settings, activate 'Leads' feature
	- Go to CRM -> Leads and create a Lead:
	- Set email field to 'aaa@test.com'
	- Click on 'Convert to opportunity'

	Neither the action or partner_id field is set to the right value.

Cause

	Due to missing 'lead_id' field in template, the partner_id field
	is not recomputed since action is not recomputed.

Solution

	Add 'lead_id' field as invisible in form.

opw-2439722
Task ID-2452777
COM PR odoo/odoo#68618