Pass extra db_stress args to fbcode crash tests (#8587)

Summary:
Allow extra arguments to be passed to db_stress in fbcode crash tests by the ```rocksdb-lego-determinator``` invoker.

Pull Request resolved: #8587

Reviewed By: zhichao-cao

Differential Revision: D29940217

Pulled By: anand1976

fbshipit-source-id: 17cbcd2def60eff2a895553f917694496c4742aa

build_tools/rocksdb-lego-determinator

@@ -1220,7 +1220,7 @@ FBCODE_STRESS_CRASH_TEST_COMMANDS="[
             {
                 'name':'Run RocksDB whitebox crash tests',
                 'timeout': 86400,
-                'shell':'cd $WORKING_DIR; mkdir /dev/shm/rocksdb_whitebox_crash_test && TEST_TMPDIR=\$(mktemp -d --tmpdir=/dev/shm/rocksdb_whitebox_crash_test) python3 rocksdb/src/tools/db_crashtest.py --stress_cmd=buck-out/dbg/gen/rocks/tools/rocks_db_stress -secondary_cache_uri=\"$SECONDARY_CACHE_URI\" --env_uri=$ENV_URI -checkpoint_one_in=0 -backup_one_in=0 -cache_size=134217728 -cache_numshardbits=4 -logtostderr=false whitebox || $CONTRUN_NAME=whitebox_crash_test $TASK_CREATION_TOOL',
+                'shell':'cd $WORKING_DIR; mkdir /dev/shm/rocksdb_whitebox_crash_test && TEST_TMPDIR=\$(mktemp -d --tmpdir=/dev/shm/rocksdb_whitebox_crash_test) python3 rocksdb/src/tools/db_crashtest.py --stress_cmd=buck-out/dbg/gen/rocks/tools/rocks_db_stress -secondary_cache_uri=\"$SECONDARY_CACHE_URI\" --env_uri=$ENV_URI -checkpoint_one_in=0 -backup_one_in=0 -cache_size=134217728 -cache_numshardbits=4 $EXTRA_DB_STRESS_ARGS -logtostderr=false whitebox || $CONTRUN_NAME=whitebox_crash_test $TASK_CREATION_TOOL',
                 'user':'root',
                 $PARSER
             },