Remove split_msg stub from log_levels (#890)

* concepts.wip exercises changed to deprecated

* Revert "concepts.wip exercises changed to deprecated"

This reverts commit 28f91a8.

* Change annelyns-infiltration slug for old version

* Revert "Change annelyns-infiltration slug for old version"

This reverts commit 09dfe5d.

* Cleanup of log-levels stubs

---------

Co-authored-by: Colin Leach <[email protected]>

Author: colinleach

exercises/concept/log-levels/log-levels.jl

@@ -1,7 +1,3 @@
-function split_msg(msg)
-
-end
-
 function message(msg)
 
 end