clean X
This function is only useful for testing.
i1 : X = specialGushelMukaiFourfold "cubic scroll" o1 = X o1 : ProjectiveVariety, GM fourfold containing a surface of degree 3 and sectional genus 0
i2 : X' = clean X o2 = X' o2 : ProjectiveVariety, GM fourfold containing a surface of degree 3 and sectional genus 0
i3 : X === X' o3 = false