Add new test cases to abc-finalize-.py
Summary:
Add new test cases and assertions.
Also replace the sync_blocks calls with a proper wait_for_tip() function.
Depends on D2161
Test Plan:
./test/functional/test_runner.py abc-finalize-block
Reviewers: deadalnix, #bitcoin_abc
Reviewed By: deadalnix, #bitcoin_abc
Subscribers: teamcity, schancel
Differential Revision: https://reviews.bitcoinabc.org/D2162