Fix missing icon shown for package actions group

[bjarnef]

Prerequisites

• I have added steps to test this contribution in the description below

Description

In #5606 <umb-icon> component was adding and the icon in the icon in header of the expansion panels was replaced with <umb-icon>.

However for package actions it wasn't rendered correct, which this PR fixes.

[bjarnef]

@nathanwoulfe maybe you would like to test this one? I guess we don't need the second part regarding setting the icon classes anyway, but in that case we might also want to clear up the other panel icons.

Panels was changed a bit before initial release of v8 as I recall, but still used here and useful in some context, e.g. in packages.

I wonder if these should be components instead like <umb-box>.

<umb-panel>
   <umb-panel-header>
      ...
   </umb-panel-header>
   <umb-panel-content>
      ...
   </umb-panel-content>
</umb-panel>

or it could be named <umb-accordion>.

//cc @nielslyngsoe

[nathanwoulfe]

@bjarnef looks like @BatJan beat you to it - he fixed this issue as part of #9054