fix: nil analytics_id/anonymous_user_id causing panics

[colesnodgrass]

• fix Error when running abctl local install on Mac arm airbyte#40745
• verify the analytics configuration keys analytics_id and anonymous_user_id are strings
  • Prior to this fix, if the keys analytics_id or anonymous_user_id existed in the analytics.yml file without a value (analytics_id:), the code would incorrectly assume that a valid key also meant a valid value and would panic if this turned out to not be the case.
• add two tests to also verify the panic existing behavior and fixed new behavior