[BUG] Crash coordinates render as NaN when they should be blank

Associated issues

This makes a few small bug fixes to the crash coordinates edit map. It:

makes the form show None when there are no crash coordinates
gives the marker default coordinates so it always show on the map when it opens
fixes an issue where the alert message about a crash not having coordinates pushes the crash map out of the card it should stay inside

Side note - i found an interesting gist about !! vs Boolean() here.

URL to test: https://deploy-preview-1448--atd-vze-staging.netlify.app/

Steps to test:

Go to https://deploy-preview-1448--atd-vze-staging.netlify.app/#/crashes/11157589 to a crash without coordinates and no crash diagram
See that the map card shows an alert and that the map is contained in the card body
Also see that the map has height even though there is no crash diagram
Click the Edit Coordinates button and see that the form shows None in both inputs
Go to https://deploy-preview-1448--atd-vze-staging.netlify.app/#/crashes/19540057 to see a crash with coordinates
Click the Edit Coordinates button and see that the form shows the coordinates of the crash
Test updating and saving any crash besides the one above without coordinates to make sure it still works. Trying to keep the example above intact. 🙏

[ ] ~Check migrations for any conflicts with latest migrations in master branch~
[ ] ~Confirm Hasura role permissions for necessary access~
[x] Code reviewed
[x] Product manager approved