Alignment with Carbon version 10.28 (#505)

* chore(deps-dev): remove @carbon/themes

* chore(deps-dev): bump devDependencies

* fix(tabs): forward click event to Tab

* feat(toggle): dispatch toggle event

* feat(tag): dispatch close event

* feat(tooltip-icon): make tooltipText slottable

* feat(dropdown): add hideLabel prop

* docs(select): add "Hidden label" example

* refactor(modal): use class directive

* feat(modal): dispatch transitionend event

* chore(deps-dev): upgrade carbon-components to 10.28.0-rc.0

* feat(date-picker): add warn state

* feat(tag): support small size variant

* fix(search): add semantic role

* feat(toolbar-search): add disabled state

* fix(composed-modal): add aria-label prop, update header semantic tags

* chore(deps-dev): upgrade carbon-components to v10.28

* docs(overflow-menu): add light variant example

* docs(link): document OutboundLink in Component API

* chore(tooltip-icon): rename slot to "tooltipText"

* docs(component-api): wrap code blocks to minimize width

* docs(aspect-ratio): remove inline outline style

* fix(tab): do not trigger focus when mounting

* docs(tabs): add reactive example

Closes #438

src/Dropdown/Dropdown.svelte

@@ -69,6 +69,9 @@
    */
   export let label = undefined;
 
+  /** Set to `true` to visually hide the label text */
+  export let hideLabel = false;
+
   /**
    * Override the default translation ids
    * @type {(id: any) => string}
@@ -145,6 +148,7 @@
       for="{id}"
       class:bx--label="{true}"
       class:bx--label--disabled="{disabled}"
+      class:bx--visually-hidden="{hideLabel}"
     >
       {titleText}
     </label>