Fix upload folder in listmonk LXC

[bvdberg01]

Note

We are meticulous when it comes to merging code into the main branch, so please understand that we may reject pull requests that do not meet the project's standards. It's never personal. Also, game-related scripts have a lower chance of being merged.

Description

Fix for not being able to upload media due to missing upload folder. Thanks, @Narkowii for finding it :).
I also updated the update script as mentioned by @MickLesk.

Type of change

Please check the relevant option(s):

• Bug fix (non-breaking change that resolves an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (a fix or feature that would cause existing functionality to change unexpectedly)
• New script (a fully functional and thoroughly tested script or set of scripts.)

Prerequisites

The following efforts must be made for the PR to be considered. Please check when completed:

• Self-review performed (I have reviewed my code, ensuring it follows established patterns and conventions)
• Testing performed (I have tested my changes, ensuring everything works as expected)
• Documentation updated (I have updated any relevant documentation)

Related Pull Requests / Discussions

#427