message: fix(table-of-contents): fix subtree observer callback
diff: @@ -320,8 +320,9 @@ class DDSTableOfContents extends HostListenerMixin(StableSelectorMixin(LitElemen
  */
  private _contentObserverCallback() {
  const shadowRoot = this.shadowRoot as ShadowRoot;
  - const defaultSlot = shadowRoot.querySelector(`.${prefix}--tableofcontents__content slot`) as HTMLSlotElement;
  - this._setTargets(Array.from(defaultSlot.assignedNodes()));
  + const allSlots = Array.from(shadowRoot.querySelectorAll(`slot`)) as HTMLSlotElement[];
  + const allSlottedNodes = allSlots.flatMap(slot => slot.assignedNodes());
  + this._setTargets(allSlottedNodes);
  }
  /**
  @@ -363,7 +364,7 @@ class DDSTableOfContents extends HostListenerMixin(StableSelectorMixin(LitElemen
  this._contentMutationObserver.disconnect();
  (event.target as HTMLSlotElement).assignedNodes().forEach(node => {
  if (node instanceof HTMLElement) {
  - this._contentMutationObserver.observe(node, { subtree: true, childList: true });
  + this._contentMutationObserver.observe(node, { subtree: true, childList: true, attributeFilter: ['name', 'data-title'] });
  }
  });
  }
  