val headers =
      Headers.Builder()
        .add("testDate", expected)
        .build()
    assertThat(headers["testDate"]).isEqualTo("Thu, 01 Jan 1970 00:00:00 GMT")
    assertThat(headers.getDate("testDate")).isEqualTo(Date(0L))
  }

  @Test fun addInstant() {
    val expected = Instant.ofEpochMilli(0L)
    val headers =
      Headers.Builder()
        .add("Test-Instant", expected)
        .build()