Emergency patch; Rust MDB driver deletes doc. with empty update.

src/routes/channels/edit_channel.rs

@@ -26,6 +26,10 @@ pub async fn req(user: User, target: Ref, data: Json<Data>) -> Result<()> {
     data.validate()
         .map_err(|error| Error::FailedValidation { error })?;
 
+    if data.name.is_none() || data.description.is_none() || data.icon.is_none() || data.remove.is_none() {
+        return Ok(())
+    }
+
     let target = target.fetch_channel().await?;
     let perm = permissions::PermissionCalculator::new(&user)
         .with_channel(&target)