124 structure make rides associated with shifts

[AthenaJenkins]

This PR updated our ride model so now it is not directly associated with a date and driver, but instead gets those data from its associated shift.
This required making small changes in many files (eg everywhere there was @ride.driver had to be changed to @ride.shift.driver)
All the rspec and cucumber tests pass, although that isn't really a guarantee the app is completely functional.

Additional changes:
This issue actually ended up being much more involved than I previously thought as I had to add completely new functionality for selecting a shift when creating a new ride. Right now you select a date, and then an ajax call collects the shifts on that date and you can associate a ride to that shift. There currently is no way to create a ride without associating it to a shift. All the javascript for this was put into a new file. A bunch of work also had to be done to get it to automatically select the right shift if you came to that page from the shift view page, but it all seems to work decently well

Also, I took the opportunity to change shift.shift_date to simply shift.date because that was bothering me.

Also I need to add tests for the new shift selection functionality

[codecov]

Codecov Report

Attention: Patch coverage is 88.46154% with 3 lines in your changes missing coverage. Please review.

Project coverage is 96.22%. Comparing base (69321d3) to head (0b697df).
Report is 92 commits behind head on main.

Files with missing lines	Patch %	Lines
app/controllers/shifts_controller.rb	57.14%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #127      +/-   ##
==========================================
- Coverage   96.91%   96.22%   -0.70%     
==========================================
  Files          27       27              
  Lines         389      397       +8     
==========================================
+ Hits          377      382       +5     
- Misses         12       15       +3     

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