[Security Solution] Set default template timelines' filter to 'timeline'

[angorayc]

Summary

https://github.com/elastic/siem-team/issues/821

How to verify this PR:

1. Click on the timeline(flyout)

2. Click on the gear

3. Select open timeline

4. Should be filtered by timeline by default "Only Timeline"

5. Switch freely on the filter and see if it filters as expected as well.

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• This was checked for keyboard-only and screenreader accessibility
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser
• This was checked for cross-browser compatibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 2784cae

Build metrics

async chunks size

id	value	diff	baseline
securitySolution	7.3MB	+157.0B	7.3MB

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@elasticmachine merge upstream