Using datetime.fromtimestamp() is returning incorrect results due to a loss of precision in the underlying EPOC time. This causes the time to return the same result for multiple seconds, and then "jump", making the seconds value not reliable.

Tested on FeatherS2 and Raspberry Pi Pico.

Steps to reproduce:

import time
import adafruit_datetime as datetime
while True:
    datetime.datetime.fromtimestamp(time.time())
    time.sleep(1)

(observe the time not change second to second)