Possible null dereference fixes

modules/ChatQuotes/Model/Quote/Result.cs

@@ -6,7 +6,7 @@ namespace West.TelegramBot.ChatQuotes.Model.Quote;
 [JsonObject(NamingStrategyType = typeof(CamelCaseNamingStrategy))]
 public class Result
 {
-    public string Image { get; set; }
+    public string Image { get; set; } = "";
     public Type Type { get; set; }
     public long Width { get; set; }
     public long Height { get; set; }

modules/UserGroupTag/Handler.cs

@@ -96,7 +96,7 @@ namespace UserGroupTag
             User user;
             if (!_userCache.TryGetValue(userId, out user))
             {
-                user = (await Bot.GetChatMemberAsync(Chat, userId)).User;
+                user = (await Bot.GetChatMemberAsync(Chat.Id, userId)).User;
                 _userCache.SetValue(userId, user, Int32.MaxValue);
             }