Allow desk workers to update whether they have office access

[fpagnoux]

Depends on https://github.com/mitoc/gear-db-django/pull/491

Test plan:

• Ensure that as a desk worker, you can give yourself the role "Office Access"
• Ensure that as a desk worker, you cannot give (or remove) yourself any other role
• Ensure that as a desk worker, you cannot give (or remove) someone else's Office Access status