Test showing cf value is lost on refresh to add attachment
Allow default CF arguments to re-populate create ticket form

As shown in the tests added in 90827a1, setting DefaultsFromTopArguments
to false blocks the reseting of supplied values when the page is
re-rendered after adding an attachment. This value was likely set in
error initially. Removing it allows the default DefaultsFromTopArguments => 1
setting which provides the correct behavior.
On Modify, MaybeRedirectForResults rather than DefaultsFromTopArguments

Remove DefaultsFromTopArguments => 0 and always take defaults from
%ARGS. To handle the case of values like CFs changing based on a scrip
firing, call MaybeRedirectForResults if the ticket is updated. This will
ensure that %ARGS is cleared if things changed in the backend.
Merge branch '4.2/retain-default-cf-value-on-refresh'