Update v3.1-RC2 schema

[richfab]

GBFS v3.1-RC2 what modified on master to fix an inconsistency in the spec (MobilityData/gbfs#845).

Update the gbfs-json-schema module to include the latest version of the v3.1-RC2 JSON Schema (MobilityData/gbfs-json-schema#191).

Example PR from last RC update: #204