remove unused Lx tracking

Remove the Lx tracking. I don't know its functionality, but it is currently not in use and has no support.

requested review from @v.friese

assigned to @se.gorbunov

Dear @d.smith, @fweig, @c.pauly, @i.selyuzhenkov, @a_meye37_AT_uni-muenster.de, @f.uhlig, @v.friese, @p.-a.loizeau, @se.gorbunov, @s.zharko, @s.lebedev, @andrey.lebedev,

you have been identified as code owner of at least one file which was changed with this merge request.

Please check the changes and approve them or request changes.

added CodeOwners label

we agreed with Volker to delete the code. It is kept in the git history and can be reanimated once needed.

merged

added Tracking label