searchCluster = function (searchTerm, clusters) {
  if (!searchTerm) { searchTerm = ''; }
  return clusters.filter((cluster) => {
    searchTerm = searchTerm.toLowerCase();
    return cluster.toLowerCase().includes(searchTerm);
  });
}
Searches cluster for a term
Looks for the term in a list of cluster

@example
'{{ searchTerm | searchCluster(cluster) }}'
this.$options.filters.searchCluster('ES1', ['ES1', 'ES2', 'ES3']);

@param {string} searchTerm The string to search for within the fields
@param {array} clusters    The list of cluster to search
@returns {array}           An array of cluster that match the search term