Update process instructions for Territory page

Why is this change being made?

Updating the instructions for requesting changes to the territory tables w/in the handbook to link to the template in the Sales Ops project and update who is responsible for updating the Sales systems. This will add clarity for the various teams on how to update this page and effectively work with operations to ensure this stays up to date.

Does this MR meet the acceptance criteria?

Conformity

• Added description to this MR explaining the reasons for the proposed change, per say-why-not-just-what