Update path for route entity.ats_candidate.settings

Problem/Motivation

The path for entity.ats_candidate.settings is /admin/structure/types/ats-candidate. Per the breadcrumb, that would make this a child page of the listing of node bundles. This is a very small issue, but it's a a little confusing. This should be a straightforward fix.

This problem also exists for the related forms (e.g. Manage fields, Manage form display, etc) but fixing the parent route should fix the children.

Steps to reproduce

1. Navigate to /admin/structure/types/ats-candidate
2. Note the breadcrumb is Home > Administration > Structure > Content types
3. Click on Content Types in the breadcrumb
4. Notes that you are on the list of node bundles
5. Likewise observe and test the breadcrumb for the various entity configuration forms (manage fields, manage form display, etc)

Proposed resolution

Change the path of the route to /admin/structure/ats-candidate