Update DFR and DCC with core Link change
This MR follows !563 (merged) and !564 (merged) . Now that those have a +1, this PR updates both the DFR and DCC after the core Link change described in #408 (closed) (DTE and DIA don't use Link so no changes there).
Following this MR will be MRs updating the credentialSubject of DFR, DCC, DTE and DIA, similar to !564 (merged) which did so for DPP.