Applies accessible accordion to contact dashboard, replaces old accordion pattern

[vingle]

Makes the contact dashboard accordions for custom fields accessible using the <details><summary> pattern. Has the added advantage of replacing a less common Civi accordion pattern .crm-collapsible (accordion3 in ThemeTest) - but achieves this by changing the class name.

Before

Custom field accordions aren't keyboard controllable

After

They are:

Technical Details

To make this match it's appearance in Grenwich, the class .crm-master-accordion-header is added to summary to make it transparent (as used accordion8).

Comments

Might impact 3rd party themes as it's changed class names, so flagging it in chat.civicrm.org/theme-maintainers .

Any extension targeting those old class names would also be impacted, tho don't know of any.

[civibot]

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[wmortada]

@vingle the logic for the accordion being opened or collapsed was inverted. I've fixed in #29091.