Add rsync package used by the tests

ubuntu_client/Dockerfile

@@ -32,7 +32,7 @@ RUN apt-get install -y build-essential git gdebi-core libcurl4 \
       #less has a foreign repo check it laterable
       nano parallel fort77 gcc gfortran-8 gdb g++ perl \
       libacl1-dev bzip2 automake autoconf libtool wget curl davix \
-      cadaver cmake createrepo cpio sqlite3
+      cadaver cmake createrepo cpio sqlite3 rsync
 
 RUN curl -sL http://storage-ci.web.cern.ch/storage-ci/storageci.key | apt-key add - && apt-get update