[vtadmin-web] Add a Select component

[doeg]

Signed-off-by: Sara Bee 855595+doeg@users.noreply.github.com

Description

selects.mov

A quick first pass at a Select component using Downshift (which is very good indeed). I expect to refine this a fair amount since I'll be adding other components (Multiselect, Combobox, etc.) that will share a lot of styling + behaviour. But this felt like a good stopping point!

I'll also note that the "Clear selection" button is a still little clunky, since it doesn't play very nicely with Downshift's exceedingly-reasonable-yet-somewhat-aggressive tabindex management. It works fine, but is not keyboard accessible.

Not staged, since #7515 is already up .

Related Issue(s)

N/A

Checklist

• Should this PR be backported? N/A
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

N/A

Impacted Areas in Vitess

Components that this PR will affect:

• Query Serving
• VReplication
• Cluster Management
• Build/CI
• VTAdmin

[ajm188]

lg2m!

[doeg]

Sorry to dismiss the approval. I pushed another small change that:

• Fix an oversight the height of the modal was always 40vh, rather that min-content
• Adds an emptyPlaceholder prop to the select component invoked when the items array is empty.