Fix: specify gatsby in the path to the front-end's public folder

[manekenpix]

Type of Change

• Bugfix: Change which fixes an issue
• New Feature: Change which adds functionality
• Documentation Update: Change which improves documentation
• UI: Change which improves UI

Description

This fixes the path the public folder when served by the backend (locally, it doesn't affect dev or prod),
This only shows up when running telescope only using docker, or when trying to access the front-end using port 3000 instead of 8000.

Checklist

• Quality: This PR builds and passes our npm test and works locally
• Tests: This PR includes thorough tests or an explanation of why it does not
• Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not (if applicable)
• Documentation: This PR includes updated/added documentation to user exposed functionality or configuration variables are added/changed or an explanation of why it does not(if applicable)