Cache duration isn't being saved in the settings UI

[arampendley]

Describe the bug

Cache duration isn't being saved in the settings UI

To Reproduce

Steps to reproduce the behavior:

1. Go to module settings
2. Click on settings
3. Click on Report Settings
4. Scroll down to Caching
5. Click Caching checkbox
6. Enter Cache the data for 10 minutes
7. Click Update

Expected behavior

10 minutes is saved in cache duration

Add me as a contributor and I will fix this.