Upgrade astral to 1.9.2

[fabaff]

Description:

Changelog: https://github.com/sffjunkie/astral/blob/master/ChangeLog.md#192---2019-01-31

Example entry for configuration.yaml (if applicable):

sun:
sensor:
  - platform: moon

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.

If the code communicates with devices, web services, or third-party tools:

• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.