Address comments from #3048

[lgoettgens]

#3048 has been merged before the review by @felix-roehrich took place. Here are his suggestions.

[felix-roehrich]

Can please update lmul and lmul! while you are at it ?
This should do the trick:

function lmul(x::WeylGroupElem, i::Integer)
  return lmul!(deepcopy(x), i)
end

function lmul!(x::WeylGroupElem, i::Integer)
  @req 1 <= i <= rank(root_system(parent(x))) "Invalid generator"
  _lmul!(parent(x).refl, word(x), UInt8(i))
  return x
end

Then you can remove the comment in ^.

[felix-roehrich]

Thanks.

[codecov]

Codecov Report

Merging #3050 (98300db) into master (ba28201) will increase coverage by 0.00%.
The diff coverage is 62.50%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3050   +/-   ##
=======================================
  Coverage   80.43%   80.44%           
=======================================
  Files         520      520           
  Lines       70114    70117    +3     
=======================================
+ Hits        56394    56403    +9     
+ Misses      13720    13714    -6     

Files	Coverage Δ
experimental/LieAlgebras/src/RootSystem.jl	41.02% <0.00%> (ø)
experimental/LieAlgebras/src/WeylGroup.jl	78.73% <71.42%> (+3.88%)	⬆️

[lgoettgens]

@simonbrandhorst As you already merged #3048, could you merge this as well?