Fix some minor stuff in the Filter component

[KarelJanVanHaute]

Add this to the component, so these buttons will work on initial load.

const clearElements = document.querySelectorAll('[data-filter-clear-elements]');
    clearElements.forEach((element) => {
      if (element instanceof HTMLElement) {
        element.addEventListener('click', (e) => {
          e.preventDefault();
          const data = JSON.parse(element.getAttribute('data-filter-clear-elements'));
          this.clearElements(data);
        });
      }
    });