Tests for user endpoint

[nicole-mcg]

A test should be created for the user endpoint.

This test will require the create_object function in file_server/util to create the objects the function needs. There is an example of this function's usage in file_server/web/endpoints/__test__/test_active_clients.py

Tests:

• Verify response has "error" key and value is "Needs auth"
• Verify name and refresh_rate keys in response are correct and there are no extra keys

An example test can be found at file_server/file/__test__/test_snapshot.py

Test naming conventions: https://pytest.readthedocs.io/en/reorganize-docs/new-docs/user/naming_conventions.html