Fix
* fix: Make class code case-insensitive and fully check Regex (1639)
* fix: Make class code case-insensitive and fully check Regex
* Allow lowercase URL too
* Merge branch &39;master&39; into class_code_fix
* Merge branch &39;master&39; into class_code_fix ([`27b731e`](https://github.com/ocadotechnology/codeforlife-portal/commit/27b731e7ed56f21b1abaac6cda30a6606333d29d))