fix: add missing export for SelectListBox element class

[web-padawan]

Description

When changing vaadin-select-list-box to not extend vaadin-list-box I added the export to the .d.ts file.
However, the corresponding JS class isn't exported, unlike SelectItem and e.g. ContextMenuListBox.

Added the export to make importing the component possible and align with other similar components.

Type of change

• Bugfix

[vursen]

Am I right in my assumption that this export exists because it's a slotted component? Because then vaadin-select-value-button should also be exported.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[web-padawan]

Am I right in my assumption that this export exists because it's a slotted component?

I think it's mainly because users can create vaadin-select-list-box manually when using renderer function / directive.
At the same time, vaadin-select-value-button and vaadin-select-overlay are not supposed to be used this way.