fix(select-input): multi select tag borders

[jonnybel]

Summary

Small adjustment to the SelectInput styles, for multi-values: When there is no multiValueRemove component being displayed (by passing an empty component to it), the multiValueLabel doesn't have a right border.
This PR fixes that, to prevent the need to also override the multiValueLabel just for this styling detail, or other "hacky" workarounds.

Before:

After:

[vercel]

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[adnasa]

One thing I've noticed is that MultiValueRemove must be a component. So either TagRemove or a div. Have you considered the possibility of accepting just null and from there passdown a dumb div to Select?

[adnasa]

nvm.. one could do this:

So basically it will work if you pass () => null to components.MultiValueRemove (or a React.Fragment)

[adnasa]

cool