As a ‘Negotiator’, I want to setup/view the 'Lettings' tab on the SMB App

[AshDeeming]

(Once #677 completed.)

Summary: As a Negotiator I should be able to make changes to my letting settings.

Given that I am a ‘Negotiator’, when I am on the ‘Lettings’ page of the app, I should then be able to perform the following:
Setup/Amend Lettings config settings

Heading: Lettings/Property Management options.
Subtext: Please amend the below options depending how your Letting business operates:.
Question : In days, how often would you like to be reminded that a tenancy is due to expire? - (field should be number only)
Question: In days, how often do you inspect your properties? (field should be number only)
Question: Your rental properties will display rent monthly as default, if you would you prefer weekly please select below? (user checkbox )

Components

Radio select component: https://dev.elements.reapit.cloud/?path=/story/radioselect--primary
Checkbox component: https://dev.elements.reapit.cloud/?path=/story/checkbox--primary