qa/workunits/cephadm/test_repos: add test for the repo commands

This isn't a great test, but it is something.

Signed-off-by: Sage Weil <sage@redhat.com>

qa/suites/rados/singleton-flat/cephadm/task/test_cephadm_repos.yaml

@@ -0,0 +1,7 @@
+roles:
+- [mon.a, mgr.x, osd.0, client.0]
+tasks:
+- workunit:
+    clients:
+      client.0:
+        - cephadm/test_repos.sh

qa/workunits/cephadm/test_repos.sh

@@ -0,0 +1,31 @@
+#!/bin/sh -ex
+
+SCRIPT_NAME=$(basename ${BASH_SOURCE[0]})
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+CEPHADM_SRC_DIR=${SCRIPT_DIR}/../../../src/cephadm
+CEPHADM=${CEPHADM_SRC_DIR}/cephadm
+
+# this is a pretty weak test, unfortunately, since the
+# package may also be in the base OS.
+function test_install_uninstall() {
+    ( sudo apt -y install cephadm && \
+	  sudo apt -y remove cephadm ) || \
+	( sudo yum -y install cephadm && \
+	      sudo yum -y remove cephadm ) || \
+	( sudo dnf -y install cephadm && \
+	      sudo dnf -y remove cephadm )
+}
+
+sudo $CEPHADM -v add-repo --release octopus
+test_install_uninstall
+sudo $CEPHADM -v rm-repo
+
+sudo $CEPHADM -v add-repo --dev master
+test_install_uninstall
+sudo $CEPHADM -v rm-repo
+
+sudo $CEPHADM -v add-repo --dev $CEPH_REF
+test_install_uninstall
+sudo $CEPHADM -v rm-repo
+
+echo OK.