Show elapsed & estimated time in batch

Hereby a patch for it:

Hi hello, I installed 3.2.x-dev version of Queue UI module on a Drupal 10.4.6 site. Then I created a queue with a simple process that took a 30 seconds to run using sleep() to slow things down. Ran my process and was able to see the regular progress text. Applied the #2 patch and reran the same queue. Was able to see the "time remaining" progress text. Then I added extra time to make the process last about an hour and reran the test. The progress text appeared but took a while to display. I had sleep(150) on each item and I guess it had to process that step before giving an estimate. Left it to run for the hour, it finished no problems. +1 for RTBC.

rakesh.regar → made their first commit to this issue’s fork.

Merged, thanks