HFP/HF PTS-Bot tests

Implemented everything available, with exceptions needing call history,
redialing, call hold/resume functionality, as well as a few tests that
failed for reasons I can't figure out.

Bug: 264637071
Test: atest pts-bot:HFP/HF
Change-Id: I203dfaf802a07a73a470181fc3a328d59c9cff84