Speed up dot with asymmetric

[blegat]

MA.broadcast!! detects Adjoint to be not mutable. With this change, XtV is a vector which is mutable so it mutates it which is faster.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.40%. Comparing base (8b058f5) to head (4348272).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #49   +/-   ##
=======================================
  Coverage   99.40%   99.40%           
=======================================
  Files          21       21           
  Lines        1171     1171           
=======================================
  Hits         1164     1164           
  Misses          7        7           

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