Adding cleanRecordPaparazzi... task to help tidy up orphaned snapshots

[nak5ive]

This adds a global task deletePaparazziSnapshots and variant-specific tasks cleanRecordPaparazzi[Debug]

A clean-record task helps identify and tidy-up orphaned snapshots after test coverage/naming changes.

[jrodbx]

FYI, this will close #529.

@jamesmosley55 explored this in the past and we had preferred an more incremental approach via https://docs.gradle.org/current/userguide/custom_tasks.html#incremental_tasks vs a delete-all-then-record approach. Imagine changing the name of test method in FormBlocker, and deleting 1000+ images and rewriting 998? Maybe I'm prematurely optimizing?

What James was exploring was creating an index of image paths when recording and checking that on rerun to do an in-memory diff, eliminating the paths that are no longer present.

Also, can we add tests as part of this PR?

[nak5ive]

Imagine changing the name of test method in FormBlocker, and deleting 1000+ images and rewriting 998? Maybe I'm prematurely optimizing?

i feel like if you're calling cleanRecordPD there's an expectation that it does this.

Also, can we add tests as part of this PR?

yep! working on that