configs/installer: increase the resource limits for all image builds

With addition of azure terraform plugins, looks like the installer builds are failing because of OOMKilled [1]

[1]: https://openshift-gce-devel.appspot.com/build/origin-ci-test/pr-logs/pull/openshift_installer/1664/pull-ci-openshift-installer-master-images/4034#operator-build-image-installer-from-the-repository

ci-operator/config/openshift/installer/openshift-installer-master.yaml

@@ -63,6 +63,36 @@ resources:
     requests:
       cpu: 100m
       memory: 200Mi
+  installer:
+    limits:
+      memory: 9Gi
+    requests:
+      cpu: "3"
+      memory: 5Gi
+  upi-installer:
+    limits:
+      memory: 9Gi
+    requests:
+      cpu: "3"
+      memory: 5Gi
+  libvirt-installer:
+    limits:
+      memory: 9Gi
+    requests:
+      cpu: "3"
+      memory: 5Gi
+  openstack-installer:
+    limits:
+      memory: 9Gi
+    requests:
+      cpu: "3"
+      memory: 5Gi
+  installer-artifacts:
+    limits:
+      memory: 9Gi
+    requests:
+      cpu: "3"
+      memory: 5Gi
   unit:
     limits:
       memory: 9Gi