fix(cart): 2222 no undefined in notifications
fix(cart): 2222 no undefined in notifications

-Bug was 'Removed undefined' appearing instead of 'Removed
[file_name]' when 1 unauthorized file removed. CartService
doesn't have file_name stored, and can't think of a nice
way to get the file name because CartController only has
1 page of names as well. So bandaid solution,
show '1 file' instead of undefined.

Closes #2222

NCI-GDC/portal-ui-legacy,NCI-GDC/portal-ui-legacy,NCI-GDC/portal-ui-legacy,NCI-GDC/portal-ui-legacy,NCI-GDC/portal-ui-legacy,NCI-GDC/portal-ui-legacy