Php8.x fixes on Main online contribution page

[eileenmcnaughton]

Overview

Php8.x fixes on Main online contribution page

Before

• notices on 'contriPriceFieldId' and 'priceset' (not page 3), undefined property _pendingAmount, various other minor notices

After

Some notices & undefined properties fix - notably the 2 above. For the first it relates to the shipped contribution page 3 - the 'other amount' field should result in the radio moving to 'other amount' when selected & clear the text amount when a radio is selected.

Technical Details

The js fix is the most siginificant in here - the approach is to move the form-specific aspects of it back to the form - this will also make it easier to reduce undefined property checks on related forms

Comments

@demeritcowboy this form hasn't had much clean up love - I tried to stop slightly short of having my soul destroyed but may not have succeeded. There is still a screed of notices - if my soul starts to grow back a bit I may try to tackle some of them

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[eileenmcnaughton]

thanks for merging @mattwire - I think this could do with someone else giving it r-run - but post merge is OK too