aries-cloudagent-python feat: drop indy sdk

Resolves #2865

This PR removes all components and tests referencing the Indy SDK library. This was accomplished by working through each module depending on the library, removing it, and then adjusting the places that referenced that module to be updated to point to replacing components.

It should be noted that the code base was already in a pretty good state; the Indy SDK dependencies were pretty neatly isolated. The "worst" of these updates was the odd test here and there that was directly using Indy SDK pieces when they should have been using things like InMemoryProfile.test_profile() or similar.

We have already ceased running tests for Indy specific components automatically in GHA. Because of this, I'm confident the removal of Indy specific tests should not cause a gap we've not already filled. However, I think this will technically result in less overall code coverage of the tests, if you were considering both the indy and non-indy tests.