Fix `when` expr of conntrack module loading (#12458)

Retrying to load conntrack modules was bound to fail due to the way, the current `when` conditions were utilized.
It was based on the assumption, that in case of success, the registered variable would have an `rc` attribute with the value `0`.
Unfortunately, the `rc` attribute is only present in case of a failure, where it's value is >1.

The result of `community.general.modprobe` in case of success looks like this:
```
{
    "changed": false,
    "msg": "All items completed",
    "results": [
        {
            "ansible_loop_var": "item",
            "changed": false,
            "failed": false,
            "invocation": {
                "module_args": {
                    "name": "nf_conntrack",
                    "params": "",
                    "persistent": "present",
                    "state": "present"
                }
            },
            "item": "nf_conntrack",
            "name": "nf_conntrack",
            "params": "",
            "state": "present"
        }
    ],
    "skipped": false
}
```

While it looks like this in case of a failure:
```
{
    "changed": false,
    "failed": true,
    "msg": "One or more items failed",
    "results": [
        {
            "ansible_loop_var": "item",
            "attempts": 3,
            "changed": false,
            "failed": true,
            "invocation": {
                "module_args": {
                    "name": "nf_conntrack_doesnotexist",
                    "params": "",
                    "persistent": "present",
                    "state": "present"
                }
            },
            "item": "nf_conntrack_doesnotexist",
            "msg": "modprobe: FATAL: Module nf_conntrack_doesnotexist not found in directory /lib/modules/5.14.0-570.32.1.el9_6.x86_64\n",
            "name": "nf_conntrack_doesnotexist",
            "params": "",
            "rc": 1,
            "state": "present",
            "stderr": "modprobe: FATAL: Module nf_conntrack_doesnotexist not found in directory /lib/modules/5.14.0-570.32.1.el9_6.x86_64\n",
            "stderr_lines": [
                "modprobe: FATAL: Module nf_conntrack_doesnotexist not found in directory /lib/modules/5.14.0-570.32.1.el9_6.x86_64"
            ],
            "stdout": "",
            "stdout_lines": []
        }
    ],
    "skipped": false
}
```

By evaluating `failed` instead, this issue can be prevented.
See also:
- https://github.com/kubernetes-sigs/kubespray/issues/11340



Co-authored-by: Max Gautier <mg@max.gautier.name>