Fix scenario where guild exists in file, but with no submissionChannel set

src/commands/challenge.rs

@@ -125,13 +125,14 @@ async fn submit(ctx: &Context, msg: &Message) -> CommandResult {
     // there are large duplicated sections that need to be merged somehow.
     let guild_data = get_guild_data();
     let guild = msg.guild_id.unwrap().as_u64().to_string();
-    if !guild_data.contains_key(&guild) {
+    let current_guild_data = &guild_data[&guild].as_object().unwrap();
+    if !guild_data.contains_key(&guild) || !current_guild_data.contains_key("submissionChannel") {
         msg.reply(&ctx.http, "Submissions aren't enabled for this server yet.").await?;
         return Ok(());
     }
-    let submission_channel = &guild_data[&guild].as_object().unwrap()["submissionChannel"].as_str().unwrap();
+    let submission_channel = current_guild_data["submissionChannel"].as_str().unwrap();
     if submission_channel != &msg.channel_id.as_u64().to_string() {
-        msg.reply(&ctx.http, format!("Sorry, submissions aren't permitted here. Please go to <#{}>. Thanks!", submission_channel)).await?;
+        msg.reply(&ctx.http, format!("Sorry, submissions aren't permitted here. Please go to <#{}>. Thanks!", guild)).await?;
         return Ok(());
     }
     if msg.attachments.len() == 0 {

src/commands/owner.rs

@@ -77,7 +77,13 @@ async fn setSubmissionChannel(ctx: &Context, msg: &Message) -> CommandResult {
     let guild = msg.guild_id.unwrap().as_u64().to_string();
     let channel = msg.channel_id.as_u64().to_string();
     if guild_data.contains_key(&guild) {
-        guild_data[&guild].as_object_mut().unwrap()["submissionChannel"] = channel.into();
+        let mut current_guild_data = guild_data[&guild].as_object().unwrap().clone();
+        if current_guild_data.contains_key("submissionChannel") {
+            current_guild_data["submissionChannel"] = channel.into();
+        } else {
+            current_guild_data.insert(String::from("submissionChannel"), channel.into());
+        }
+        guild_data[&guild] = current_guild_data.into();
     } else {
         guild_data.insert(guild, json!({
             "submissionChannel": channel