fix(decision): add --no-cache to another uv command

[jcristau]

We don't want to leave a root-owned cache in the worker user's HOME directory.

[jcristau]

Verified that the generated decision image doesn't have root-owned stuff in /builds/docker anymore:

root@53686a944a52:/# ls -la /builds/worker/
total 24
drwxr-xr-x 3 worker worker 4096 Oct  8 14:22 .
drwxr-xr-x 3 root   root   4096 Oct  8 14:22 ..
-rw-r--r-- 1 worker worker  220 Mar 29  2024 .bash_logout
-rw-r--r-- 1 worker worker 3526 Mar 29  2024 .bashrc
-rw-r--r-- 1 worker worker  807 Mar 29  2024 .profile
drwxr-xr-x 2 worker worker 4096 Oct  8 14:22 artifacts

[jcristau]

Bah, this is not enough, see https://firefox-ci-tc.services.mozilla.com/tasks/PiXh8GIQR1-NJSIGeJw9xQ/runs/0/logs/public/logs/live_backing.log

[pip-install 2024-10-16T11:13:03.385Z] executing ['uv', 'pip', 'install', '--python', '/usr/bin/python3', '--break-system-packages', '--require-hashes', '-r', '/builds/worker/checkouts/vcs/taskcluster/requirements.txt']
[pip-install 2024-10-16T11:13:03.437Z] error: failed to create file `/tmp/uv-b17927aca3d28934.lock`
[pip-install 2024-10-16T11:13:03.438Z]   Caused by: Permission denied (os error 13)

[ahal]

That looks like a separate issue, so I think we can still merge this PR

[ahal]

Thanks, I didn't think export would create a cache dir :/

[ahal]

The codecov failure is a 503 on their end.