[CI] Canary is hanging-up

### Description

Despite recently upping the timeout to 60 minutes, canary runs occasionally get stuck.

Since it happens with legacy tests (where we do not timeout command execution) we unfortunately have very little information.

TestCopyToContainer and TestCopyFromContainer do finish.

Presumably, another `container` test is stuck.

https://github.com/containerd/nerdctl/actions/runs/15838570010/job/44647113095?pr=4359

Two things could be done:
- continue rewriting container tests
- diff the hung build with the list of tests from a successful build to figure out which one is the offending test

### Steps to reproduce the issue

1.
2.
3.

### Describe the results you received and expected

Not hang

### What version of nerdctl are you using?

main

### Are you using a variant of nerdctl? (e.g., Rancher Desktop)

None

### Host information

_No response_