The probability of collision when adding an addrman entry is
expected to be 1/2^16 = 1/65536 for an address from a different /16.

This change hopes to avoid these collisions by adding 1 tried entry before adding 1 new table one, instead of 2 tried entries followed by 2 new entries, which appears to have caused a collision in the CI.

./test/functional/test_runner.py feature_asmap