tests

Add hint how to deal with scmsync-nobranch scenarios #636

Job	Run time
unit - read only fixtures	22s
unit (registry.fedoraproject.org/fedora:38)	1m 3s
unit (registry.fedoraproject.org/fedora:39)	51s
unit (registry.fedoraproject.org/fedora:rawhide)	34s
unit (registry.opensuse.org/opensuse/leap:15.3)	1m 33s
unit (registry.opensuse.org/opensuse/leap:15.4)	1m 29s
unit (registry.opensuse.org/opensuse/leap:15.5)	1m 30s
unit (registry.opensuse.org/opensuse/tumbleweed)	1m 3s
unit (quay.io/centos/centos:stream9)	28s
unit (docker.io/library/debian:stable)	27s
unit (docker.io/library/debian:unstable)	33s
unit (docker.io/library/ubuntu:latest)	29s
behave	6m 13s
	16m 35s

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