Observed behavior (please include a screenshot if possible)

When a calendar exception is created and "No service" is selected in the "Run the following schedules" drop-down menu, no records are created in calendar_dates.txt in the GTFS export to remove all calendars that need to be removed.

Expected behavior

In the GTFS export, calendar_dates.txt should contain the correct records removing all services for the dates specified in the exception.

Steps to reproduce the problem

1. Run datatools via Docker
2. Create a new GTFS feed with the editor
3. Create a calendar
4. Create an exception with type "No service"
5. Create a trip using the calendar created in step 3.
6. Take a snapshot and export it.
7. Calendar_dates will either be missing alltogether if the exception created in step 4 is the only one, or will be present but will not contain the exception created in step 4.

Any special notes on configuration used

Running via Docker with authentication disabled.

Version of datatools-ui and datatools-server if applicable (exact commit hash or branch name)

Server 8889e0
UI 1efb3f0