Seconds are not displayed in the hover-over info box

In the hover-over info box on the feeds page, the PHPFINA feed start time is currently displayed as a date time string (see #1032) but it is missing the vital seconds bit and only displays whole seconds. can we have seconds please?  (assuming the date/time string to to stay)

(See https://community.openenergymonitor.org/t/thoughts-on-the-new-input-and-feed-page-layouts/8583?u=pb66)