Math.MatMul: should only allow count relationship between columns of first matrix, and lines of second matrix

[ccfontes]

Describe the bug
Matrix product in Math.MatMul allows incompatible count relationship between columns of first matrix, and lines of second matrix.

To Reproduce

[@f4(1 2 3 4) @f4(5 6 7 8)] | Math.MatMul([@f4(9 10 11 12) @f4(13 14 15 16)])
;=> [(59 78 97 116) (83 110 137 164) (0 0 0 0) (0 0 0 0)]

first matrix: columns=4
second matrix: lines=2

Expected behavior
The number of columns in the first matrix should be equal to the number of lines in the second matrix.