Fix upgrade on participant_register date

[eileenmcnaughton]

Overview

On testing I found the conversion routing on participant register date wasn't working properly when
upgrading to 5.15 - this fixes

Before

Jcalendar groups are stored with hard-date formatted fields in participant_register_date_low & high and then a relative format in the relative dates array

After

For relative dates relative_dates array & the high & low fields should be empty. participant_register_date_relative should be handled

Technical Details

@seamuslee001 can you take a look at this - it could be a potentially regression about to hit 5.15 if not resolved before it's cut but my brain has stopped processing it. I have lot of groups & they have names which meant something once but now I can't figure out whether old new smartgroup should be the same as 'a bit newer group' or more like 'old group but not as old as old group'

Comments

@mattwire I think you merged the upgrade but I guess neither of us tested well

[civibot]

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[seamuslee001]

I have tested this i created 2 smart groups 1 with an explicit date range and one with a relative date range, I then switched the code and confirmed that loading the form to update the smart group was broken for both, then ran the db upgrades, confirmed that the upgrade correctly restored the register date fields

[eileenmcnaughton]

thanks @seamuslee001 that was playing on my mind