Extend GlDatepicker with predefined date ranges

Problem to solve

In VSA: [UX] Usability improvements - adding prede... (gitlab-org/gitlab#408656 - closed) we added predefined date ranges for VSA. We want to enhance this to provide a better user experience by integrating the date picker into the dropdown as per the screenshot below:

Implementation guide

• Update the dropdown text to display the full date range text (perhaps some CSS tweaks needed to get this right)
• Extend the dropdown to include the start and end calendars
• Add prop to opt-out of the new GlDatepicker behaviour
• GitLab project changes will happen in gitlab-org/gitlab#419049

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Description

Figma file

View design specs in Figma →

Checklist

Make sure the following are completed before closing the issue:

1. Assign the correct component label to this issue.
2. Create an MR with the additions or updates needed.
3. Be sure to get your MR reviewed by a FE/UX Foundations designer.
4. When applicable, create an MR in Pajamas to update the demos. If you do not have capacity to complete the demos, create an issue in Pajamas and bring the issue to your team planning session for prioritization and scheduling. Mark the issue as related to this one.
5. When applicable, create an MR in Pajamas to update the component status.
6. When applicable, create an issue in Pajamas using the "Component Documentation" issue template to update guidelines. Ping a designer on your team for awareness and bring the issue to your team planning meeting for prioritization and scheduling.
7. When applicable, create an issue in Pajamas using the "Figma update" issue template to update the Figma UI Kit. Ping a designer on your team for awareness and bring the issue to your team planning meeting for prioritization and scheduling.
8. When introducing a major or breaking change, communicate the changes within the Engineering Week in Review.
9. 🎉 Congrats, you made it! You can now close this issue.