Rationalise date formatting

[eileenmcnaughton]

Overview

Rationalise date formatting

Before

Various places hard code the date format - ie

CRM_Utils_Date::customFormat($membershipOb->end_date, '%B %E%f, %Y')

After

simpler syntax that (I think) makes the formatting taking place clearer (along with code comments) CRM_Utils_Date::formatDateOnlyLong($membershipOb->start_date)

Technical Details

This came out of discovering a place in the code was 'accidentally formatted correctly'
and finding it far too hard to figure out the right way to specify the date formatting -
something that seems confirmed by finding various places with hard-coded date formatting
rather than using the setting

Comments

There are some other places that aren't hard-coding but could be switched over

[civibot]

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[seamuslee001]

Test fail relate https://test.civicrm.org/job/CiviCRM-Core-PR/37562/testReport/(root)/CRM_Member_Form_MembershipTest/testSubmitRecur/

[eileenmcnaughton]

Test should be fixed now...

[eileenmcnaughton]

@seamuslee001 it has passed now

[seamuslee001]

Looks fine to me merging