Timestamp from Date fails with non-zero milliseconds

[prowe]

If the Timestamp(Date) constructor is invoked with a Date that includes non-zero milliseconds then it will throw an error with the milliseconds out of range:

Error: Seconds 945 must be between 0 inclusive, and 60 exclusive

To reproduce:

it('constructor with Date that has milliseconds', () => {
      const date = new Date(2000, 0, 1, 12, 30, 45, 900);
      let timestamp = new ion.Timestamp(date);
      assert.equal(timestamp.getSecondsDecimal(), new ion.Decimal('45.900'));
});