Time should be shown in the timezone the browser is in, not the server.

[dcorbin]

Describe the bug
All my servers run on UTC. Octoprint is no exception. The plugin seems to show the ETA in UTC, rather than the timezone the client (browser) is in. It should use the browser's local time.

To Reproduce
Steps to reproduce the behavior:

1. Set your server timezone to UTC
2. Print something
3. Access Octoprint from a browser not in UTC.
4. It shows the incorrect time. (correct for UTC).

Expected behavior
It should show the time in the local time of the browser.

Environment information:

• Octoprint Version: 1.9.3
• Browser: Firefox: 124.0.2
• Python Version: 3.9.2