Summary:
The ParallelIO/DBBasicTestWithParallelIO.MultiGet/11 test fails if Snappy compression library is not installed, since RocksDB defaults to Snappy if none is specified. So dynamically determine the supported compression types and pick the first one.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6038

Differential Revision: D18532370

Pulled By: anand1976

fbshipit-source-id: a0a735114d1f8892ea09f7c4af8688d7bcc5b075