Comment # 2 on bug 1215943 from Martin Loviska

The check-config script is reading /proc/config.gz [1], therefore using zgrep
[2].

In DVD test suite the installer pulls busybox-gzip instead of gzip package.

```
2023-10-06 00:44:42 <1> install(3735) [zypp::exec++]
forkspawnengine.cc(start):274 Executing[C] 'rpm' '--root' '/mnt' '--dbpath'
'/var/lib/rpm' '-U' '--percent' '--noglob' '--excludedocs' '--force' '--nodeps'
'--'
'/mnt/var/cache/zypp/packages/openSUSE-MicroOS-20231005-0/noarch/busybox-gzip-1.36.1-30.1.noarch.rpm'
2023-10-06 00:44:42 <1> install(3735) [Ruby]
modules/PackageSlideShow.rb(PkgInstallDone):405 Installed package busybox-gzip
2023-10-06 00:44:42 <1> install(3735) [zypp-core] PathInfo.cc(unlink):706
unlink
/mnt/var/cache/zypp/packages/openSUSE-MicroOS-20231005-0/noarch/busybox-gzip-1.36.1-30.1.noarch.rpm
```

Replacing busybox-gzip by gzip fixes the issue.

```
cat: /sys/kernel/security/apparmor/profiles: No such file or directory         
                                                                               
                                            [37/741]

Verifying binaries in
/var/lib/rancher/k3s/data/3dfc950bd39d2e2b435291ab8c1333aa6051fcaf46325aee898819f3b99d4b21/bin:
- sha256sum: good
- links: good

System:
- /sbin iptables v1.8.9 (legacy): ok
- swap: disabled
- routes: ok

Limits:
- /proc/sys/kernel/keys/root_maxkeys: 1000000

info: reading kernel config from /proc/config.gz ...

Generally Necessary:
- cgroup hierarchy: cgroups V2 mounted, cpu|cpuset|memory controllers status:
good
- CONFIG_NAMESPACES: enabled
- CONFIG_NET_NS: enabled
- CONFIG_PID_NS: enabled
- CONFIG_IPC_NS: enabled
- CONFIG_UTS_NS: enabled
- CONFIG_CGROUPS: enabled
- CONFIG_CGROUP_PIDS: enabled
...
```

[1] https://github.com/k3s-io/k3s/blob/master/contrib/util/check-config.sh#L14
[2] https://github.com/k3s-io/k3s/blob/master/contrib/util/check-config.sh#L36