Splunk component filter support

[asleeis]

Description:

Adding "filter" support for the Splunk component. Filter implementation is modeled after the current HomeKit component filter support. This is the THIRD PR for this. First attempt was screwy in terms of commit information, and couldn't figure out how to resolve with prior PR, so started over. Second had a long pause while I found the time to figure out how to write the test cases. This time, everything should be ready to go with little delay (hopefully).

Pull request with documentation for home-assistant.io (if applicable): TBD; need to create; will update

Example entry for configuration.yaml (if applicable):

splunk:
  token: XXXXXXXXXXX
  host: splunk.example.com
  port: 8088
  ssl: true
  verify_ssl: false
  name: homeassistant
  filter:
    exclude_domains:
      - automation

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.
• I have followed the development checklist

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in home-assistant.io : Add documentation for Splunk Component entity filter support home-assistant.io#9831

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

• No changes to communication code.

If the code does not interact with devices:

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

[MartinHjelmare]

mock_requests isn't used in this function. We don't need to pass it here. It's active in the test, that's enough.

[asleeis]

Thanks. Missed that. I originally started trying to model my setup after another used for this component. I eventually deviated and went a whole other way (taking out use of mock_requests). Updated.

[MartinHjelmare]

Thanks!

[asleeis]

Sweet. Thanks!