[C++][FlightRPC] <grpcpp/version_info.h> not found

[rok]

Describe the bug, including details regarding any error messages, version, and platform.

Originally posted by @adamreeve in #49990 (comment):

It looks like this change has caused a failure in the ARM64 Ubuntu 22.04 C++ builds: https://github.com/apache/arrow/actions/runs/26138794569/job/76879676231#step:8:3834

In file included from /arrow/cpp/src/arrow/flight/flight_internals_test.cc:34:
/arrow/cpp/src/arrow/flight/transport/grpc/util_internal.h:20:10: fatal error: grpcpp/version_info.h: No such file or directory
   20 | #include <grpcpp/version_info.h>
      |          ^~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.

Component(s)

C++, FlightRPC

[kou]

Issue resolved by pull request 50001
#50001