code: public final @NotNull S isGreaterThanOrEqualTo(@Nullable T other) {
      isNotNull();
      if (actual.compareTo(other) >= 0) {
        return myself();
      }
      failIfCustomMessageIsSet();
      throw failure(unexpectedLessThan(actual, other));
    }
docs: Verifies that the actual {@link Comparable} is greater than or equal to the given one.
  
  @param other the given value.
  @return this assertion object.
  @throws AssertionError if the actual {@code Comparable} is {@code null}.
  @throws AssertionError if the actual {@code Comparable} is not greater than or equal to the given one.