Upgrade async_timeout to 1.3.0

[fabaff]

1.3.0

• Don't suppress nested exception on timeout. Exception context points on cancelled line with suspended await
• Introduce .timeout property
• Add methods for using as async context manager

Example entry for configuration.yaml (if applicable):

http:

Checklist:

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

• Local tests with tox run successfully. Your PR cannot be merged unless tests pass
• New dependencies have been added to the REQUIREMENTS variable ([example][ex-requir]).
• New dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.

[mention-bot]

@fabaff, thanks for your PR! By analyzing the history of the files in this pull request, we identified @robbiet480, @balloob and @rmkraus to be potential reviewers.