[pytx] Experiment with Querying PDQ Rotations Natively

[Dcallies]

PDQ and the pdqhash binding have a native "generate all rotations" hash method. In previous PRs, we experimented with rotating the image itself, but it is much faster to use the native rotation function.

This change will be involved, as we only need to hash rotations some of the time, and not all the time. For SignalTypes that support it without any overhead, querying by rotations should probably be the default.

Tasks

• Add new "SignalTypeWithNativeRotations" mixin interface
  • It should have a separate hash_with_rotations(file-like-object IO[bytes])
    • This should return a dict of RotationType -> str hash
• Adjust the SignalTypeIndex to use rotations by default if the SignalType supports it
  • It needs to at least work for PDQ
  • Adjust the default index match type also include the rotation, which should be included in the native __str__() method for debugging