more dead code removal

[araujoms]

The methods for * are redundant, as LinearAlgebra redirects them to the specialized mul! calls.

Removing Poynomials again as apparently it got added back accidentally through all the PRs.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 70.48%. Comparing base (31fd0c3) to head (0699bef).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #254      +/-   ##
==========================================
+ Coverage   69.38%   70.48%   +1.10%     
==========================================
  Files          54       54              
  Lines        2365     2294      -71     
==========================================
- Hits         1641     1617      -24     
+ Misses        724      677      -47     

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