Summary:
- Fix cmake build failure with gflags.
- Add CI tests for both gflags 2.1 and 2.2.
- Fix ctest config with gtest.
- Add CI to run test with ctest.
One benefit of ctest is it support timeout, it's set to 5min in our CI, so we will know which test is hang.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8324
Test Plan: CI pass
Reviewed By: ajkr
Differential Revision: D28762517
Pulled By: jay-zhuang
fbshipit-source-id: 09063c5af5f9f33abfcdeb48593acbd9826cd199