container: run dnf check in container for dnf4/dnf5 compat

[mvo5]

This is an alternative idea to PR#651 - we run dnf inside the
container to init the dnf system. However with dnf5 this no
longer works and it just throws an error.

So instead we run dnf check which should work on both dnf{4,5}.

---

test: move target-arch-smoke testcases to Fedora42 (for
dnf5)

This will give us testing for dnf5 as well.

[draft until tests are good and I double checked dnf sources]

[ondrejbudai]

It works just fine with dnf 4:

# time dnf check
Updating Subscription Management repositories.

________________________________________________________
Executed in    1.80 secs      fish           external
   usr time    8.23 millis  229.00 micros    8.00 millis
   sys time   17.53 millis  333.00 micros   17.20 millis

However, it's quite slow with dnf 5:

# time dnf check

________________________________________________________
Executed in   24.95 secs      fish           external
   usr time    5.38 millis  314.00 micros    5.07 millis
   sys time    9.21 millis   37.00 micros    9.17 millis

[mvo5]

It works just fine with dnf 4:

# time dnf check
Updating Subscription Management repositories.

________________________________________________________
Executed in    1.80 secs      fish           external
   usr time    8.23 millis  229.00 micros    8.00 millis
   sys time   17.53 millis  333.00 micros   17.20 millis

However, it's quite slow with dnf 5:

# time dnf check

________________________________________________________
Executed in   24.95 secs      fish           external
   usr time    5.38 millis  314.00 micros    5.07 millis
   sys time    9.21 millis   37.00 micros    9.17 millis

Thanks for checking this ! I switched now to use dnf check --duplicates which takes around 1s for me compared to the 20s the dnf check takes with dnf5. That seems like a reasonable compromise(?).

[ondrejbudai]

Checked on my system, works like a charm! Thanks!