v1.9.1 Patch Release

What's Changed

• Allow omit rpc input/output for optimization by @longquanzheng in #390
• Support local activity optimization by @longquanzheng in #389
• Use omit empty for ExecuteRpcSignalRequest model by @longquanzheng in #392
• Use timer duration to replace firingTimestamp for timerCommand by @longquanzheng in #393
• Add local activity test and truncate unnecessary error response by @longquanzheng in #395

Full Changelog: v1.9.0...v1.9.1