[REF] minor tidy ups on very nasty function

[eileenmcnaughton]

Overview

Changes

• switches to using cached function rather than deprecated function to get MembershipTypeDetails (covered by existing tests)
• remove unnecessary date formatting

Before

Nasty

After

Still nasty if I'm honest

Technical Details

It used to be necessary to ISO format code before DAO->save. However, along the line wee fixed it lower
down & no longer need this smattered all over the code. Test proves it's OK (actually they noisily pointed out that the code had to stop unpacking the separated string as it was now getting that done for it :-)

Comments

[civibot]

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[yashodha]

@eileenmcnaughton You might want to squash your commits.

[eileenmcnaughton]

@yashodha I wasn't going to on this one because the 3 commits do different things - but I could squash the first 2 I guess since that's just the test plus the fix that follows

[eileenmcnaughton]

Ok test squashed into the commit it tests

[colemanw]

Looks good.