mathlib

8f7971ae - refactor(linear_algebra/bilinear_form): Change namespace of is_refl, is_symm, and is_alt (#10338)

refactor(linear_algebra/bilinear_form): Change namespace of is_refl, is_symm, and is_alt (#10338) The propositions `is_refl`, `is_symm`, and `is_alt` are now in the namespace `bilin_form`. Moreover, `is_sym` is now renamed to `is_symm`.