Added pytest to tumbleweed docker file

dockerfiles/tumbleweed.docker

@@ -23,6 +23,8 @@ RUN zypper refresh && \
     zypper install -y netcat-openbsd && \
     zypper install -y nano && \
     zypper install -y vim && \
+    zypper install -y python2-pytest && \
+    zypper install -y python3pytest && \
     useradd -u 30996 msk_jenkins && \
     ln -sfn /usr/lib64/libzmq.so.5 /usr/lib64/libzmq.so.3