Fix OpenSUSE image build

Change-Id: I17e72e8239a5f4c0875e6ff736ca74393e86284c

.zuul.yaml

@@ -82,7 +82,6 @@
 - job:
     name: spyglass-docker-build-gate-opensuse
     timeout: 1800
-    voting: false
     run: tools/gate/playbooks/docker-image-build.yaml
     nodeset: spyglass-single-node
     vars:
@@ -129,7 +128,6 @@
 - job:
     name: spyglass-docker-publish-opensuse
     timeout: 1800
-    voting: false
     run: tools/gate/playbooks/docker-image-build.yaml
     nodeset: spyglass-single-node
     secrets:

images/spyglass/Dockerfile.opensuse_15

@@ -17,14 +17,15 @@ RUN set -x \
          curl \
          gcc \
          git-core \
+         python3 \
          python3-dbm \
          python3-devel \
          python3-pip \
          python3-setuptools \
          which \
     && zypper --non-interactive --no-gpg-checks ar -f https://download.opensuse.org/repositories/devel:languages:python/openSUSE_Leap_15.1/devel:languages:python.repo \
-    && zypper --non-interactive --no-gpg-checks install python3-six-1.12.0-lp151.80.1.noarch \
-    && python3 -m pip install -U pip \
+    && zypper --non-interactive --no-gpg-checks install python3-six-1.12.0-lp151.80.1.noarch
+RUN pip3 install -U pip \
     && zypper clean -a \
     && rm -rf \
          /tmp/* \