Wifi/WifiAware NetworkSpecifier: Stop storing uid/packageName

The uid/packageName is stored in the container NetworkRequest object.
Hence, this info will still be available to WifiNetworkFactory for
it's usages.

Note: Setting the uid/package name in the capabilities of the
network agent will restrict access to the created networks.

Bug: 144102365
Test: atest android.net.wifi
Test: Verified that wifi network request related CTS verifier tests
pass.
Change-Id: Ibb2ca652fa510343efd0352578c3d0b2b6f2dbb0