Installs Required Packages for pgo-scheduler

When building the 'pgo-scheduler' image using ubi8-minimal, the
'findutils' and 'procps' packages are now installed.  This ensures the
'find' utility is present as required by the scheduler's liveness
probe, while also ensuring the 'pgrep' and 'pidof' utilities are
present as required by the scheduler's 'start.sh' script.

Author: andrewlecuyer

build/pgo-scheduler/Dockerfile

@@ -3,6 +3,7 @@ ARG BASEVER
 ARG PREFIX
 FROM ${PREFIX}/pgo-base:${BASEOS}-${BASEVER}
 
+ARG BASEOS
 ARG PGVERSION
 ARG BACKREST_VERSION
 ARG PACKAGER
@@ -30,6 +31,13 @@ RUN if [ "$DFSET" = "rhel" ] ; then \
 	&& chown -R 2:2 /opt/cpm /pgo-config ; \
 fi
 
+RUN if  [ "$BASEOS" = "ubi8" ]; then \
+    ${PACKAGER} -y install \
+        findutils \
+        procps \
+    && ${PACKAGER} -y clean all ; \
+fi
+
 ADD bin/pgo-scheduler /opt/cpm/bin
 ADD installers/ansible/roles/pgo-operator/files/pgo-configs /default-pgo-config
 ADD conf/postgres-operator/pgo.yaml /default-pgo-config/pgo.yaml