bump go-swagger to v0.28.0 (#463)

hack/tools/go.mod

hack/tools/go.sum

pkg/generated/models/alpine_v001_schema.go

pkg/generated/models/helm_v001_schema.go

pkg/generated/models/intoto_v001_schema.go

pkg/generated/models/jar_v001_schema.go

pkg/generated/models/log_entry.go

pkg/generated/models/rekord_v001_schema.go

pkg/generated/models/rfc3161_v001_schema.go

pkg/generated/models/rpm_v001_schema.go

pkg/generated/models/search_index.go

pkg/generated/models/search_log_query.go

pkg/generated/models/tuf_v001_schema.go

pkg/generated/restapi/server.go