respec.yaml: use older Ubuntu

[ralfhandl]

Respec depends on puppeteer which has a problem with the latest Ubuntu

Tick one of the following options:

• schema changes are included in this pull request
• schema changes are needed for this pull request but not done yet
• no schema changes are needed for this pull request

[lornajane]

Is there any chance of resolving the problem at some point? I can see that changing the ubuntu version helps us in the short term, but are there some details of the wider problem?

[baywet]

Feedback from the meeting.
Here is some additional context:

• https://github.com/puppeteer/puppeteer/blob/main/docs/troubleshooting.md#issues-with-apparmor-on-ubuntu
• https://chromium.googlesource.com/chromium/src/+/main/docs/security/apparmor-userns-restrictions.md

It might be worth exploring whether any upstream fix is in the works (pupeteer, respec, etc...) or whether settings can solve that (instead of staying back on the agent version).

@ralfhandl to add another issue to open for discussion

[duncanbeevers]

Here's a troubleshooting from Puppeteer about Ubuntu 23 and App Shield.
https://github.com/puppeteer/puppeteer/blob/main/docs/troubleshooting.md#issues-with-apparmor-on-ubuntu

Here's the Chromium documentation describing the Chromium + AppArmor interactions, along with a few possible workarounds.

https://chromium.googlesource.com/chromium/src/+/main/docs/security/apparmor-userns-restrictions.md

[ralfhandl]

Alternative that runs with latest ubuntu:

• Run respec without sandbox #4358