[WifiCandidates] Include networkId in key fields

We could have the same ssid/sectype/bssid combo show up for two
or more different configs. Retain all of them as candidates.

Bug: 112196799
Test: atest WifiCandidatesTest
Change-Id: I4a15d0c5a2e45de80850c9d17e2e6e303c661b0b
2 files changed