Images don't show up when hugo build doesn't use a baseURL

[jputrino]

Describe the bug

In builds that don't provide a hugo baseURL flag, the product icons and other images used in the site header and footer return 404s. This has to do with how Hugo constructs URLs based on where an image file resides in the site file structure.

To reproduce

Steps to reproduce the behavior:

1. Open any Netlify deploy preview (not branch deploy) or a preview site in CloudCannon
2. Verify that the icons are missing

The image below is from a preview in CloudCannon:

Expected behavior

The icons should appear regardless of the options fed to the hugo build command.

Additional context