Add rdiv!, ldiv! methods and tests

[dmbates]

• add LinearAlgebra.rdiv! method for TriangularRFP [rdiv! for TriangularRFP #18]
• change ldiv! to LinearAlgebra.ldiv!
• add tests for ldiv! and rdiv!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.39%. Comparing base (5cadbff) to head (cb23c40).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #19      +/-   ##
==========================================
+ Coverage   97.28%   97.39%   +0.11%     
==========================================
  Files           6        5       -1     
  Lines         184      192       +8     
==========================================
+ Hits          179      187       +8     
  Misses          5        5              

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[dmbates]

Looks like I should add tests for ldiv! and rdiv! for with transposed A. I will do that. Any other changes?

[dmbates]

@andreasnoack Could you review this PR please? I haven't bumped the version yet. Do you think these methods should be documented or is the fact that they exist and are documented for triangular matrices sufficient?

[andreasnoack]

I think it's fine to rely on the existing docstrings as the interface is exactly the same. It is only the storage layout that is different and it is abstracted away.