Simplify fetching client member

src/tools/discord.ts

@@ -15,7 +15,7 @@ export async function getGuildChannel(guildID: string, channelID: string): Promi
 
 export async function getChannelPermission(channel: GuildTextBasedChannel): Promise<Readonly<PermissionsBitField> | null> {
     try {
-        const guildMember = await channel.guild.members.fetch(client.user!.id);
+        const guildMember = await channel.guild.members.fetchMe();
         if (!guildMember) return null;
 
         return channel.permissionsFor(guildMember);