Improve error messages

[TheAnnalyst]

Currently, some of the error messages are fairly difficult for an end user to understand. Some of this might have to be fixed in frc-scouting instead.

[joeljose]

Could you please elaborate the work?

[TheAnnalyst]

You'd probably want to try inputting bad data on the Add Match page, and then if you get a confusing or unclear error message, find a way to clarify it.