Merge pull request #91 from dalbodeule/develop

apiDiscordRoutes fix. (11x)

webserver/src/main/kotlin/space/mori/chzzk_bot/webserver/utils/DiscordGuildCache.kt

@@ -31,6 +31,7 @@ object DiscordGuildCache {
                     guild = cache[guildId]
                 }
                 try {
+                    if(guild == null) { return null }
                     if (guild!!.guild.roles.isEmpty()) {
                         guild!!.guild.roles = fetchGuildRoles(guildId)
                     }