Fix syntax error (!) in db_crashtest.py (#6207)

Summary:
Fixes syntax error from https://github.com/facebook/rocksdb/pull/6203

Pull Request resolved: https://github.com/facebook/rocksdb/pull/6207

Test Plan: make blackbox_crash_test -> no more syntax error

Differential Revision: D19161752

Pulled By: pdillinger

fbshipit-source-id: b3032f296041ab56307762622b9ef6c03a8379aa

tools/db_crashtest.py

@@ -97,7 +97,6 @@ default_params = {
     "max_write_batch_group_size_bytes" : lambda: random.choice(
         [16, 64, 1024 * 1024, 16 * 1024 * 1024]),
     "level_compaction_dynamic_level_bytes" : True,
-        [t * 16384 if t < 3 else 1024 * 1024 * 1024 for t in range(1,30)]),
     "verify_checksum_one_in": 1000000
 }