[REF] Standardise form handling in the Find Pledges search form

[seamuslee001]

Overview

This standardises the form handling in the Find Pledges search form

Before

Transient style of handling form values

After

consolidated function to handle form values

ping @eileenmcnaughton @demeritcowboy

[civibot]

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[demeritcowboy]

Did an r-run and looks ok just a few things not sure if they're expected to work in urls with force=1?

• Contact-related fields, e.g. the sort_name field works, but not contact_tags or contact_type.
• pledge_acknowledge_date_is_not_null doesn't seem to work (the one at the bottom of the form about acknowledgement sent). I also tried it using CIVICRM_QFID_1_pledge_acknowledge_date_is_not_null.

But they all work fine using the form itself.

[seamuslee001]

@demeritcowboy certainly the latter hasn't been converted to metadata and the former i don't believe the other fields have been added yet for metadata apart from sort_name

[seamuslee001]

Test fail is unrelated and i'm going to merge this based on @demeritcowboy 's testing