fix(ui5-panel): add missing dependency for ui5-icon

[Psidium]

When importing the ui5-panel by itself, it would not be able to load the ui5-icon that it makes use of.

Example:

Rendering the panel with

<ui5-panel width="100%" accesible-role="Complementary"></ui5-panel>

Without the fix:

With this fix, it works as expected:

Also, I did not find how to test this implementation.

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[ilhan007]

Hello @Psidium
thanks for your finding and proposal. In addition to the Icon import (you already did), could you also do the following:

replace line 278:
await fetchResourceBundle("@ui5/webcomponents");

with:
await Promise.all([
fetchResourceBundle("@ui5/webcomponents");
Icon.define(),
]);

As the Panel depends on the Icon, it should await for the Icon`s define.