Include oslo_reports in installation of heat

Heat depends on oslo.reports but does not install it by default.

A previous commit reverted a pip install of this dependency, but
the Heat RPM isn't fixed upstream.

Change-Id: Idab85e6b2d0b158dfdd97edddfbaf305f55be37d

docker/centos/binary/heat/heat-base/Dockerfile

 FROM %%KOLLA_NAMESPACE%%/%%KOLLA_PREFIX%%base:%%KOLLA_TAG%%
 MAINTAINER Kolla Project (https://launchpad.net/kolla)
 
+RUN yum -y install \
+    python-oslo-reports \
+    && yum clean all
+
 COPY config-heat.sh /opt/kolla/