Function for base change matrix between two forms

[danielrademacher]

Given for example two symplectic forms of the same dimension, one can use

basechange1 := BaseChangeToCanonical(form1);
basechange2 := BaseChangeToCanonical(form2);

to compute the base change matrices to the standard form. Afterwards, one can compute a base change matrix between the two forms by multiplying the base change matrices. I think that it would be great if there would be a function to compute the base change matrix between the two forms directly, e.g.

BaseChangeMatrixBetweenForms(form1,form2);