Remove manual connection to remote

As seen in https://github.com/libgit2/libgit2/blob/master/src/remote.c#L2381-L2397

Author: Therzok

LibGit2Sharp/Core/NativeMethods.cs

@@ -1026,9 +1026,6 @@ internal static extern int git_remote_delete(
             RepositorySafeHandle repo,
             [MarshalAs(UnmanagedType.CustomMarshaler, MarshalCookie = UniqueId.UniqueIdentifier, MarshalTypeRef = typeof(StrictUtf8Marshaler))] string name);
 
-        [DllImport(libgit2)]
-        internal static extern void git_remote_disconnect(RemoteSafeHandle remote);
-
         [DllImport(libgit2)]
         internal static extern int git_remote_fetch(
             RemoteSafeHandle remote,

LibGit2Sharp/Core/Proxy.cs

@@ -2032,14 +2032,6 @@ public static void git_remote_delete(RepositorySafeHandle repo, string name)
             }
         }
 
-        public static void git_remote_disconnect(RemoteSafeHandle remote)
-        {
-            using (ThreadAffinity())
-            {
-                NativeMethods.git_remote_disconnect(remote);
-            }
-        }
-
         public static GitRefSpecHandle git_remote_get_refspec(RemoteSafeHandle remote, int n)
         {
             return NativeMethods.git_remote_get_refspec(remote, (UIntPtr)n);

LibGit2Sharp/Network.cs

@@ -248,19 +248,11 @@ public virtual void Push(
                 GitRemoteCallbacks gitCallbacks = callbacks.GenerateCallbacks();
                 Proxy.git_remote_set_callbacks(remoteHandle, ref gitCallbacks);
 
-                try
-                {
-                    Proxy.git_remote_connect(remoteHandle, GitDirection.Push);
-                    Proxy.git_remote_push(remoteHandle, pushRefSpecs,
-                        new GitPushOptions()
-                        {
-                            PackbuilderDegreeOfParallelism = pushOptions.PackbuilderDegreeOfParallelism
-                        });
-                }
-                finally
-                {
-                    Proxy.git_remote_disconnect(remoteHandle);
-                }
+                Proxy.git_remote_push(remoteHandle, pushRefSpecs,
+                    new GitPushOptions()
+                    {
+                        PackbuilderDegreeOfParallelism = pushOptions.PackbuilderDegreeOfParallelism
+                    });
             }
         }