E2E: fix column parsing for dynamic host volumes test

In #25185 we changed the output of `volume status` to include both DHV and CSI
volumes by default. When the E2E test parses the output, it's not expecting the
new section header.

Ref: #25185

e2e/dynamic_host_volumes/dynamic_host_volumes_test.go

@@ -98,7 +98,10 @@ func TestDynamicHostVolumes_RegisterWorkflow(t *testing.T) {
 
 	out, err := e2eutil.Command("nomad", "volume", "status", "-verbose", "-type", "host")
 	must.NoError(t, err)
-	vols, err := e2eutil.ParseColumns(out)
+
+	section, err := e2eutil.GetSection(out, "Dynamic Host Volumes")
+	must.NoError(t, err)
+	vols, err := e2eutil.ParseColumns(section)
 	must.NoError(t, err)
 
 	var volID string