code: public static Tags concat(@Nullable Iterable<? extends Tag> tags, @Nullable String... keyValues) {
          return Tags.of(tags).and(keyValues);
      }
docs: Return a new {@code Tags} instance by concatenating the specified tags and key/value pairs.
  
  @param tags      the first set of tags
  @param keyValues the additional key/value pairs to add
  @return the merged tags