Switched graph to use new top nav

[lizozom]

Summary

Switched Graph to use new top nav directive, as part of #39981

Dev Docs \ QA

Graph used kbnTopNav.currentKey to indicate and store the active UI component (even if it's not inside the top nav at all). While deprecating this behavior, I had changed the implementation behind the following buttons:

Should open the field choice view:

Should toggle the field config views:

Should collapse previously opened top menus:

Checklist

Use strikethroughs to remove checklist items you don't feel are applicable to this PR.

• This was checked for cross-browser compatibility, including a check against IE11
• 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

For maintainers

• This was checked for breaking API changes and was labeled appropriately
• This includes a feature addition or change that requires a release note and was labeled appropriately

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request