Summary:
This is to fix special logic to run tests inside FB.
Buck test is broken after moving to cpp_unittest(). Move c_test back to the previous approach.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7076
Test Plan: Watch the Sandcastle run
Reviewed By: ajkr
Differential Revision: D22370096
fbshipit-source-id: 4a464d0903f2c76ae2de3a8ad373ffc9bedec64c