Default cycle analytics duration chart stage filter to all items selected

Default cycle analytics duration chart stage filter to all items selected

This is part of !14996 (merged)

Screenshots

This was the expected behaviour from the beginning but only the label reflected All stages - the actual dropdown items weren't selected by default when expanding the list.

All stages	X selected	1 selected	none selected

Does this MR meet the acceptance criteria?

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• [-] Changelog entry
• [-] Documentation (if required)
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• [-] Merge request performance guidelines
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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

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