Fix unit tests to run on R

Modules fixed:
1. com.android.server.wifi.WifiApConfigStoreTest

Bug: 182571509
Test: atest -c com.android.server.wifi.WifiApConfigStoreTest on R device
Test: atest -c com.android.server.wifi.WifiApConfigStoreTest on S device
Change-Id: I926be105ffb253ff9f97f99fb1a7bfe8b4c4b1e7
1 file changed