Update module golang/protobuf to v1.5.1

go.mod

go.sum

vendor/github.com/golang/protobuf/proto/registry.go

vendor/github.com/golang/protobuf/ptypes/any.go

vendor/github.com/golang/protobuf/ptypes/doc.go

vendor/github.com/golang/protobuf/ptypes/duration.go

vendor/github.com/golang/protobuf/ptypes/timestamp.go

...r/google.golang.org/protobuf/encoding/protojson/decode.go

...r/google.golang.org/protobuf/encoding/protojson/encode.go

...olang.org/protobuf/encoding/protojson/well_known_types.go

...r/google.golang.org/protobuf/encoding/prototext/decode.go

...r/google.golang.org/protobuf/encoding/prototext/encode.go

...r/google.golang.org/protobuf/internal/descfmt/stringer.go

...google.golang.org/protobuf/internal/detectknown/detect.go

vendor/google.golang.org/protobuf/internal/detrand/rand.go

...olang.org/protobuf/internal/encoding/json/decode_token.go

...g.org/protobuf/internal/encoding/messageset/messageset.go

...r/google.golang.org/protobuf/internal/encoding/tag/tag.go

...ogle.golang.org/protobuf/internal/encoding/text/encode.go

...r/google.golang.org/protobuf/internal/fieldnum/api_gen.go