fix: Remove obsolete methods and properties (#1849)

* Remove obsolete methods and properties

* Remove rest of GuildEmbed

* Remove TokenType.User

* Changes regarding the removal of the user tokentype

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -79,7 +79,6 @@ namespace Discord.API
         {
             return tokenType switch
             {
-                default(TokenType) => token,
                 TokenType.Bot => $"Bot {token}",
                 TokenType.Bearer => $"Bearer {token}",
                 _ => throw new ArgumentException(message: "Unknown OAuth token type.", paramName: nameof(tokenType)),

src/Discord.Net.Rest/Entities/Guilds/RestGuild.cs

@@ -90,8 +90,6 @@ namespace Discord.Rest
         /// <inheritdoc />
         public DateTimeOffset CreatedAt => SnowflakeUtils.FromSnowflake(Id);
 
-        [Obsolete("DefaultChannelId is deprecated, use GetDefaultChannelAsync")]
-        public ulong DefaultChannelId => Id;
         /// <inheritdoc />
         public string IconUrl => CDN.GetGuildIconUrl(Id, IconId);
         /// <inheritdoc />

src/Discord.Net.Rest/Entities/Invites/RestInviteMetadata.cs

@@ -8,9 +8,6 @@ namespace Discord.Rest
     {
         private long _createdAtTicks;
 
-        /// <inheritdoc />
-        [Obsolete("This property doesn't exist anymore and shouldn't be used.")]
-        public bool IsRevoked { get; private set; }
         /// <inheritdoc />
         public bool IsTemporary { get; private set; }
         /// <inheritdoc />