fix: replace removed OkHttp internal OkHostnameVerifier with platform default

Signed-off-by: Jesus Recio <jrecio@izertis.com>

Author: jesmrec

owncloudComLibrary/src/main/java/com/owncloud/android/lib/common/network/KnownServersHostnameVerifier.java

@@ -19,7 +19,7 @@
 package com.owncloud.android.lib.common.network;
 
 import android.content.Context;
-import okhttp3.internal.tls.OkHostnameVerifier;
+import javax.net.ssl.HttpsURLConnection;
 import timber.log.Timber;
 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.SSLPeerUnverifiedException;
@@ -33,7 +33,7 @@ public class KnownServersHostnameVerifier implements HostnameVerifier {
     private final HostnameVerifier mDelegate;
 
     public KnownServersHostnameVerifier(Context context) {
-        this(context, OkHostnameVerifier.INSTANCE);
+        this(context, HttpsURLConnection.getDefaultHostnameVerifier());
     }
 
     KnownServersHostnameVerifier(Context context, HostnameVerifier delegate) {