Reachability - Remove AdHoc TEst /reachabilityForLocalWiFi

[jamesmontemagno]

Per apple docs this will no longer work when on a local wifi :(

https://developer.apple.com/library/content/samplecode/Reachability/Listings/ReadMe_md.html#//apple_ref/doc/uid/DTS40007324-ReadMe_md-DontLinkElementID_11

Fixed this inside connectivity plugin

[conceptdev]

for context see #106

@jamesmontemagno is this the change you mean?
https://github.com/jamesmontemagno/ConnectivityPlugin/blob/a1e9f18c525782d0c87635b9e743028d15a82a29/src/Connectivity.Plugin.iOSUnified/Reachability.cs#L138-L176

[jamesmontemagno]

Yup! Was it removed in #106? This needs to be removed: https://github.com/xamarin/ios-samples/blob/master/ReachabilitySample/reachability.cs#L61-L73