flatbuffers

Support `--conform` for vector of unions (#6883)

Typo fixes in comments of flatbuffers.h and flexbuffers.h (#6901)

[Java] Prevent generation of enum names when underlying type is long (#6781) (#6895)

[C++] Fix memory leak when using grpc (#6896) (#6897)

Output errors / warnings on stderr instead of stdout (#6881)