cephfs admin: disable test TestCancelClone on quincy

This test feels very flaky, only passing 2-3 times out of ten (by
my vague guesstimate). This needs investigation.
However I don't want to block all of CI against quincy for this this
now.

Signed-off-by: John Mulligan <jmulligan@redhat.com>

cephfs/admin/clone_test.go

@@ -143,6 +143,10 @@ func TestCloneSubVolumeSnapshot(t *testing.T) {
 }
 
 func TestCancelClone(t *testing.T) {
+	if serverVersion == cephQuincy {
+		t.Skipf("temporarily disabled on quincy: very flaky")
+	}
+
 	fsa := getFSAdmin(t)
 	volume := "cephfs"
 	group := "Park"