Simplify asReference

ts/editor/editor-toolbar/OptionsButton.svelte

@@ -27,10 +27,9 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     placement="bottom"
     inline
     on:close={() => (showFloating = false)}
-    let:asReference
 >
-    <span use:asReference>
     <IconButton
+        slot="reference"
         tooltip={tr.actionsOptions()}
         --border-left-radius="5px"
         --border-right-radius="5px"
@@ -38,7 +37,6 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     >
         {@html cogIcon}
     </IconButton>
-    </span>
 
     <Popover slot="floating" --popover-padding-inline="0">
         <DropdownItem on:click={toggleShrinkImages}>