code: function cleanAvailableUpdates(updates) {
          return updates.reduce(function (arr, updateInfo) {
              var extDefinition = extensions[updateInfo.id];
              if (!extDefinition || !extDefinition.installInfo) {
                  // extension has been uninstalled in the meantime
                  return arr;
              }
  
              var installedVersion = extDefinition.installInfo.metadata.version;
              if (semver.lt(installedVersion, updateInfo.registryVersion)) {
                  arr.push(updateInfo);
              }
  
              return arr;
          }, []);
      }
docs: Takes the array returned from getAvailableUpdates() as an input and removes those entries
  that are no longer current - when currently installed version of an extension
  is equal or newer than registryVersion returned by getAvailableUpdates().
  This function is designed to work without the necessity to download extension registry
  @param {Array.<{id: string, installVersion: string, registryVersion: string}>} updates
  previous output of getAvailableUpdates()
  @return {Array.<{id: string, installVersion: string, registryVersion: string}>}
  filtered input as function description