Update concordium-contracts-common with company Attribute tags

[limemloh]

concordium-contracts-common contains constants for the possible attribute tags used by the identity objects, this list is missing company related attributes.
The list of attributes can be found here https://docs.google.com/spreadsheets/d/1CxpFvtAoUcylHQyeBtRBaRt1zsibtpmQOVsk7bsHPGA/edit#gid=0