CHANGELOG.md in benchmark_driver-0.10.1 vs CHANGELOG.md in benchmark_driver-0.10.2

@@ -1,4 +1,8 @@
+# v0.10.2
+
+- Optionalize `working_directory` of "command\_stdout" runner
+
 # v0.10.1
 
 - Add "command\_stdout" runner to plug in existing benchmark
 - Explicitly bump supported Ruby version to >= 2.2
   - v0.10.0 actually does not work with 2.1