Replacing require.nil in model package (#16953)

* Replacing require.nil in model package

* Fixing tests

* Update model/file_info_test.go

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

* Update model/file_info_test.go

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>
Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

model/websocket_client_test.go

@@ -22,7 +22,7 @@ func dummyWebsocketHandler(t *testing.T) http.HandlerFunc {
 			WriteBufferSize: 1024,
 		}
 		conn, err := upgrader.Upgrade(w, req, nil)
-		require.Nil(t, err)
+		require.NoError(t, err)
 		var buf []byte
 		for {
 			_, buf, err = conn.ReadMessage()