Add authentication to error log endpoint

[balloob]

Description:

Require authentication when fetching the raw error log.

Does not require a frontend change as frontend already calls API using auth.

Related issue (if applicable): Reported by Matt Hamilton.

Example entry for configuration.yaml (if applicable):

api:

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass

If the code does not interact with devices:

• Tests have been added to verify that the new code works.

[pvizeli]

Yeah that is a security issue

[Eriner]

Thanks for the quick response and resolution @balloob!