Crash due to dual linking of gflags

[zhztheplayer]

Bug description

ERROR: something wrong with flag 'flagfile' in file '/root/velox4j/src/main/cpp/build/_deps/gflags-src/src/gflags.cc'.  One possibility: file '/root/velox4j/src/main/cpp/build/_deps/gflags-src/src/gflags.cc' is being linked both statically and dynamically into this executable.

This is because this workaround is not working when BUILD_SHARED_LIBS is cached.

Changing the workaround to unset(BUILD_SHARED_LIBS CACHE) will solve the issue though it may affect cache reads on the variable afterwards.

System information

Velox System Info v0.0.2
Commit: fd3ab044a600b8d0e2b5605bb4ca823968bf84a5
CMake Version: 3.28.3
System: Linux-5.4.0-200-generic
Arch: x86_64
C++ Compiler: /usr/bin/c++
C++ Compiler Version: 11.2.1
C Compiler: /usr/bin/cc
C Compiler Version: 11.2.1
CMake Prefix Path: /usr/local;/usr;/;/usr/local/lib64/python3.6/site-packages/cmake/data;/usr/local;/usr/X11R6;/usr/pkg;/opt