Improved copying of bill of materials formulas

Previously, when copying a bill of materials from a finished product to a semi-finished product, the 'sales bill of materials formulas' were also copied. However, these only have value on the finished product. This caused an error message when deleting these formulas under a semi-finished product. This has now been resolved by no longer copying the 'sales bill of materials formulas' when copying to a semi-finished product.