REALMS: Make Description required, decrease Environment text area height and move it below Description

Similar to STAFF-349 and STAFF-364, it would be great if the environment text area would be positioned the same way for REALMS as it is right now for MC and MCL: Smaller and below the "Description" field.

Currently many tickets just have all the information in the environment field, and leave the description field empty or don't put any valuable information in it.

It might even be worth it to remove the field completely for REALMS, as the project is mainly about server issues.