Fix memory leak in OptionsTest::OptionsComposeDecompose

Summary:
Fixing asan error.
Closes https://github.com/facebook/rocksdb/pull/2887

Differential Revision: D5838895

Pulled By: yiwu-arbug

fbshipit-source-id: 1662ce9856eb5e6877675347dc2240f2acb6fae8

options/options_test.cc

@@ -676,6 +676,7 @@ TEST_F(OptionsTest, OptionsComposeDecompose) {
 
   ASSERT_OK(RocksDBOptionsParser::VerifyDBOptions(base_db_opts, new_db_opts));
   ASSERT_OK(RocksDBOptionsParser::VerifyCFOptions(base_cf_opts, new_cf_opts));
+  delete new_cf_opts.compaction_filter;
 }
 
 TEST_F(OptionsTest, ColumnFamilyOptionsSerialization) {