Performance issues with sl-select and a high number of sl-options

[kirchsuSICKAG]

Describe the bug

When using the sl-select with a high number of sl-options, it takes some time until the sl-select is done with rendering.

Demo

See following codepen, where I added 4000 options to a select and it takes quite some time until the select is finished with rendering:
https://codepen.io/kirchsuSICKAG/pen/gbYmrmJ?editors=1010

Browser / OS

• OS: all
• Browser: all
• Browser version: [e.g. 22]

Additional information

This problem occurs since shoelace version 2.19.0 with the fix of #1971
It can be fixed by not triggering the "handleDefaultSlotChange" of the select for the initial loading.

I am willing to provide a PR for this problem.