test/system: Fix 260-sdnotify being silently skipped

[ricardobranco777]

Fix 260-sdnotify being silently skipped since podman v5.7.1

PODMAN_CMD is uninitialized until basic_setup() runs, causing podman_runtime() to invoke an empty command and fall back to [null].

Call basic_setup() before the runtime check to ensure PODMAN_CMD is populated before use.

Otherwise all the tests are silently skipped:

• https://api.cirrus-ci.com/v1/artifact/task/5685948077309952/html/sys-podman-fedora-42-root-host.log.html
• https://openqa-assets.opensuse.org/tests/5821036/file/podman-bats-root-local.tap.txt

ok 507 sdnotify : ignore # skip this test only works with crun, not [null]
ok 508 sdnotify : conmon # skip this test only works with crun, not [null]
ok 509 sdnotify : container # skip this test only works with crun, not [null]
ok 510 sdnotify : healthy # skip this test only works with crun, not [null]
ok 511 sdnotify : play kube - no policies # skip this test only works with crun, not [null]
ok 512 sdnotify : play kube - with policies # skip this test only works with crun, not [null]
ok 513 podman kube play - exit-code propagation # skip this test only works with crun, not [null]
ok 514 podman pull - EXTEND_TIMEOUT_USEC # skip this test only works with crun, not [null]
ok 515 podman system service # skip this test only works with crun, not [null]

Checklist

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  for more information.
• Referenced issues using Fixes: #00000 in commit message (if applicable)
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• Release note entered in the section below (or None if no user-facing changes)

Does this PR introduce a user-facing change?

None

[ricardobranco777]

Verification run:

• root: https://openqa-assets.opensuse.org/tests/5822127/file/podman-bats-root-local.tap.txt
• rootless: https://openqa-assets.opensuse.org/tests/5822127/file/podman-bats-user-local.tap.txt

[lsm5]

LGTM

@containers/podman-maintainers PTAL

[baude]

LGTM