feat(samples): add issuingSoftware block to v0.7.0 sample credentials
This MR adds the optional issuingSoftware block to all v0.7.0 verifiable credential samples so they exercise the new schema (!756 (merged)) and context (!757 (merged)).
This MR adds the optional issuingSoftware block to all v0.7.0 verifiable credential samples so they exercise the new schema (!756 (merged)) and context (!757 (merged)).