Ability to set minimum interval when using "Auto" for time based widgets

## What?

Graylog widgets allow you to choose a data point interval, or use "auto". Auto is very helpful for zooming in/out of time based widgets, however, in some cases this can cause charts to not display any lines.

For example, if i have logs with 1 data point every 30s, and i zoom in too much, the lines disappear. Setting a minimum interval would allow the use of auto but not allow it to go below a specified interval:


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## Why?

Having the ability to set a minimum allows "Interval: Auto" to be more flexible and avoid issues where no data points are visible on the widget.

## Your Environment

* Graylog Version: 5.1.1
* ~~Elasticsearch~~ OpenSearch Version: 2.6.0
* MongoDB Version: 6.0.6
* Operating System: Ubuntu Server 22.04 LTS
* Browser version: Google Chrome Version 114.0.5735.90 (Official Build) (arm64)

Please let me know if there are any questions. This isn't particularly important and not anything that a customer or prospect has asked about, just something i've run into when using time based widgets.