Resolve "Increase toast duration for created work item"

What does this MR do and why?

Increase create work item toast (Epic/Issue created) delay to keep it visible for 10s instead of 5s.

This task depends on this change in the gitlab-ui project.

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Screenshots or screen recordings

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Before	After
Is visible for 5s	Is visible for 10s

How to set up and validate locally

1. Go to the /work_items or /epic page (with WI flag enabled)
2. Click on create new item
3. Expect a modal to show up to create the work item
4. After submitting the new item, expect a toast appears saying it was created
5. Expect that the toast stays visible for 10s then automatically closes

Related to #483104

Blocked by gitlab-ui!4729