fix error on GRPC Python - ignore namespace tree if not specified (#5862) (#5922)
fix error on GRPC Python - ignore namespace tree if not specified (#5862) (#5922)


pjulien/flatbuffers,pjulien/flatbuffers,google/flatbuffers,alexames/flatbuffers,google/flatbuffers,pjulien/flatbuffers,google/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,google/flatbuffers,pjulien/flatbuffers,pjulien/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,google/flatbuffers,google/flatbuffers,google/flatbuffers,evolutional/flatbuffers,DavadDi/flatbuffers,evolutional/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,DavadDi/flatbuffers,DavadDi/flatbuffers,google/flatbuffers,pjulien/flatbuffers,google/flatbuffers,evolutional/flatbuffers,google/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,pjulien/flatbuffers,google/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,google/flatbuffers,alexames/flatbuffers,google/flatbuffers,pjulien/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,DavadDi/flatbuffers,DavadDi/flatbuffers,pjulien/flatbuffers,google/flatbuffers,pjulien/flatbuffers,pjulien/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,DavadDi/flatbuffers,evolutional/flatbuffers,pjulien/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,evolutional/flatbuffers,google/flatbuffers