Support the multiple DoB formats used by sample UG inputs

[kennsippell]

• There are hundreds of values in the format 13/2/1985 and hundreds in the format 1977-08-14. Currently we only support the latter. Should we support both?

Originally posted by @kennsippell in #38

[jonathanbataire]

Kenn this would cause a nightmare dealing with data in psql lets stick to yyyy-mm-dd
there were mistakes during unvalidated user creation hence these various formats

[jonathanbataire]

ignore if in the json it shows up as yyyy-mm-dd and this is just for the ui and template :)

[kennsippell]

@jonathanbataire This is the accepted input for DoB, but the output will always be in ISO format yyyy-mm-dd.
Can see here in the unit test, the inputs are different but the outputs are the same.