title: Extracting epoch from two different days yields same result
body: <p>If I run this query on my database</p>
  <pre><code>SELECT EXTRACT('epoch' FROM age('2021-01-01'::date, '2019-12-01'::date))
  </code></pre>
  <p>The result is <code>34149600</code>.</p>
  <p>But then if I try with 2019-12-02 (one day more)</p>
  <pre><code>SELECT EXTRACT('epoch' FROM age('2021-01-01'::date, '2019-12-02'::date))
  </code></pre>
  <p>The result is exactly the same <code>34149600</code>!</p>
  <p>As if the seconds passed from 02 december 2019  to 01 january 2021 are the same as the seconds passed from 01 december 2019 to 01 january 2021.</p>
  <p>Why is this? I've already tried the above code with timezones on 00:00:00+00 timezone for all dates (for 1st january 2021, 1st december 2019 and 2nd december 2021), and it gives the same result</p>
  <p>Obviously, I would have expected the epoch to be different, around 3600*24 of difference (seconds in a day).</p>