Unify DynamicContext callback parameters across link click, button click and form tracking plugins in v5 release

[matus-tomlein]

Suggested in #1389 (review):

It's unfortunate we couldn't fit this into v4 as a breaking change, the resulting API inconsistency with the other plugins will be a bit awkward to resolve now.

Plugin	Context Arg 1	Context Arg 2	Context Arg 3
Button	Event Payload	- (Element in this PR)	-
Link	Element	-	-
Form (Change/Focus)	Element	Element Type	Element Value
Form (Submit)	Element	ElementData[]	-

It might be worth planning for v5 to unify plugins onto a single object param for dynamic contexts so we can be a bit looser with the interface. For Link and Button at least, getting the actual MouseEvent/PointerEvent for information on the type of click, modifier keys, coordinates, pressure used, etc could be useful in some use cases (as suggested in #1368) so would be nice to add in at some point.

Originally posted by @jethron in #1389 (review)