test: Fix e2e docker writing files as root on Linux

[mattrunyon]

I think this only affects Linux from what I could find online.

Essentially, Docker creates volume directories as root if the directory doesn't exist on the host machine. It also runs and writes files as root, so even if you create the directory ahead of time, the files are still owned by root. This is really annoying if you run say npm run e2e:docker and then npm run e2e:ui to start in headed mode because running outside of Docker can't write to the directories it needs to. You then need to sudo rm -r test-results playwright-report and possibly some snapshot files at times if you change tests.

This should fix all of that and offer a prompt to fix the directories if they aren't owned by you when you run with Docker. After that, snapshots should work smoothly and write all the files as your user instead of root.

[mofojed]

Tried running e2e tests and updating snapshots on my Ubuntu machine, seemed to work fine.

[mofojed]

On Mac getting some errors when running:

4: unable to create directory '/.cache/dconf': Permission denied.  dconf will not work properly.
      - [pid=2379][err] [Parent 2379, Main Thread] WARNING: unable to create directory '/.cache/dconf': Permission denied.  dconf will not work properly.: 'glib warning', file /home/pwuser/firefox/toolkit/xre/nsSigHandlers.cpp:187
      - [pid=2379][err] 
      - [pid=2379][err] (firefox-default:2379): dconf-CRITICAL **: 14:24:42.184: unable to create directory '/.cache/dconf': Permission denied.  dconf will not work properly.

Seems like this might be related: microsoft/playwright#16491 (comment)

[mofojed]

Just removing my approval as there's some issues on Mac