fixed executable name in command line help

CHANGELOG.md

@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Fixed
+- Fixed executable name in command line help
 
 ## [0.1.0] - 2020-05-08
 ### Added

Dockerfile

@@ -51,4 +51,4 @@ COPY --from=build $SOURCE_DIR_PATH $SOURCE_DIR_PATH
 ARG VIRTUALENV_PATH
 ENV PATH=$VIRTUALENV_PATH/bin:$PATH
 ENTRYPOINT ["tini", "--"]
-CMD ["switchbot-mqtt"]
+CMD ["switchbot-mqtt", "--help"]

switchbot_mqtt/__init__.py

@@ -136,7 +136,7 @@ def _main() -> None:
         datefmt="%Y-%m-%dT%H:%M:%S%z",
     )
     argparser = argparse.ArgumentParser(
-        "MQTT client controlling SwitchBot button automators, "
+        description="MQTT client controlling SwitchBot button automators, "
         "compatible with home-assistant.io's MQTT Switch platform"
     )
     argparser.add_argument("--mqtt-host", type=str, required=True)