[WifiScoreReport] Use tx retries as well as tx bad for adjustment

Devices have implemented the tx-bad counters quite differently;
bring in the retry count as well to dilute the difference.
(Also more correct in principle, when counters are properly
implemented).

Also, reset the adjustment on the reset() call, and add a unit
test that would have caught this bug.

Bug: 74613347
Test: Unit tests
Change-Id: Ice6ccdf39c6d222a89733d2e61e1f3c26116ebb7
2 files changed