ci: fix coverage report artifact upload

[mas-who]

Done

Fix issue with coverage report artifact upload failing due to build files for monaco-editor containing invalid characters.

QA

1. Run the LXD-UI:
   • On the demo server via the link posted by @webteam-app below. This is only available for PRs created by collaborators of the repo. Ask @mas-who or @edlerd for access.
   • With a local copy of this branch, run as described here.
2. Perform the following QA steps:
   • Ensure CI passes

[webteam-app]

Demo

Jenkins

demos.haus

[mas-who]

Added some steps to show directory contents within the runner environment. Also updated node to 20 for the coverage job. I think it's still worthwhile to enable manual dispatch for coverage, since it's difficult to replicate the issue, we might need to try a few things and iterate on the main branch

[mas-who]

just doing a test quick on the fork, will merge after

[edlerd]

LGTM, hope this fixes it 🤞

[mas-who]

LGTM, hope this fixes it 🤞

I was able to replicate the issue on my fork and this fixed it there, so chance is high but let's see 😅