test: Attach criu dump log on checkpoint failures

Occasionally, `crun checkpoint` fails in Fedora 41 podman upstream PRs
(in revdeps tests). This isn't otherwise reproducible,  so start with
collecting all information. The journal just says "Please check
CRIU logfile", so let's collect that.

test/check-application

@@ -1539,11 +1539,19 @@ class TestApplication(testlib.MachineCase):
             b.wait_not_present(".pf-v5-c-modal-box")
 
         if self.has_criu:
-            b.wait(lambda: self.getContainerAttr("swamped-crate", "State") in NOT_RUNNING)
-            b.wait_text(
-                f'#containers-containers tr:contains("{IMG_BUSYBOX}") dt:contains("Latest checkpoint") + dd',
-                'less than a minute ago'
-            )
+            try:
+                b.wait(lambda: self.getContainerAttr("swamped-crate", "State") in NOT_RUNNING)
+                b.wait_text(
+                    f'#containers-containers tr:contains("{IMG_BUSYBOX}") dt:contains("Latest checkpoint") + dd',
+                    'less than a minute ago'
+                )
+            except testlib.Error:
+                # dump.log may help with debugging criu failures
+                attachment = self.label() + "-dump.log"
+                dump_log = m.execute("find /var/lib/containers -name dump.log").strip()
+                m.download(dump_log, attachment, ".")
+                testlib.attach(attachment, move=True)
+                raise
         else:
             # expect proper error message
             b.wait_in_text(".pf-v5-c-alert.pf-m-danger", "Failed to checkpoint container swamped-crate")