tests: increase reruns and reruns delay in pytest

In order to avoid false positive in the CI that I've been unable to
reproduce elsewhere than in the CI.

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>
(cherry picked from commit 8d0b3b4)

tests/tox.sh

@@ -114,7 +114,7 @@ ansible-playbook -vv -i "$CEPH_ANSIBLE_SCENARIO_PATH"/hosts "$TOXINIDIR"/ceph-an
 ansible-playbook -vv -i "$CEPH_ANSIBLE_SCENARIO_PATH"/hosts "$TOXINIDIR"/ceph-ansible/tests/functional/setup.yml
 ansible-playbook -vv -i "$CEPH_ANSIBLE_SCENARIO_PATH"/hosts "$TOXINIDIR"/ceph-ansible/site-container.yml.sample --extra-vars="ceph_docker_image_tag=latest-pacific ceph_docker_registry=$REGISTRY_ADDRESS ceph_docker_image=ceph/daemon"
 
-py.test --reruns 5 --reruns-delay 10 -n 8 --sudo -v --connection=ansible --ansible-inventory="$CEPH_ANSIBLE_SCENARIO_PATH"/hosts --ssh-config="$CEPH_ANSIBLE_SCENARIO_PATH"/vagrant_ssh_config "$TOXINIDIR"/ceph-ansible/tests/functional/tests
+py.test --reruns 20 --reruns-delay 3 -n 8 --sudo -v --connection=ansible --ansible-inventory="$CEPH_ANSIBLE_SCENARIO_PATH"/hosts --ssh-config="$CEPH_ANSIBLE_SCENARIO_PATH"/vagrant_ssh_config "$TOXINIDIR"/ceph-ansible/tests/functional/tests
 
 # teardown
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