Propagate use_string_pooling in CopyTable (#5879)
Propagate use_string_pooling in CopyTable (#5879)

This allows using CopyTable for deduplicating strings.
pjulien/flatbuffers,alexames/flatbuffers,google/flatbuffers,pjulien/flatbuffers,pjulien/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,pjulien/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,DavadDi/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,google/flatbuffers,google/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,pjulien/flatbuffers,google/flatbuffers,alexames/flatbuffers,pjulien/flatbuffers,google/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,alexames/flatbuffers,google/flatbuffers,pjulien/flatbuffers,pjulien/flatbuffers,pjulien/flatbuffers,evolutional/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,evolutional/flatbuffers,pjulien/flatbuffers,evolutional/flatbuffers,google/flatbuffers,alexames/flatbuffers,DavadDi/flatbuffers,pjulien/flatbuffers,DavadDi/flatbuffers,evolutional/flatbuffers,google/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,google/flatbuffers,DavadDi/flatbuffers,google/flatbuffers,google/flatbuffers,DavadDi/flatbuffers,evolutional/flatbuffers,google/flatbuffers,google/flatbuffers,google/flatbuffers,evolutional/flatbuffers,alexames/flatbuffers,DavadDi/flatbuffers,google/flatbuffers,pjulien/flatbuffers