v1.4.0

What's Changed

• Fix activity finalizer by @seregazhuk in #205
• Add the ability to mock activities in tests by @seregazhuk in #208
• Do not pass the nullable result to marshaller by @kafkiansky in #210
• Bugfix: Set data converter to failure #206 by @seregazhuk in #212
• Use RR kv only for testing by @seregazhuk in #214
• Fix: don't fail on null workflow result history by @seregazhuk in #215
• Enum as input for workflow by @cv65kr in #216

Full Changelog: v1.3.7...v1.4.0