ci-operator/templates/openshift/installer/cluster-launch-installer-*: Drop *_REGION from teardown

These came in with d00da5d (templates/openshift/installer: Add
azure cluster test configuration, 2019-05-23, #3877), but the
installer should be extracting the region from metadata.json [1,2].

[1]: https://github.com/openshift/installer/blob/d9a9648cf2330d467cca9f2988846d031464125e/pkg/types/aws/metadata.go#L5
[2]: https://github.com/openshift/installer/blob/d9a9648cf2330d467cca9f2988846d031464125e/pkg/types/azure/metadata.go#L5

Author: wking

ci-operator/templates/openshift/installer/cluster-launch-installer-e2e.yaml

@@ -917,12 +917,8 @@ objects:
         value: ${CLUSTER_TYPE}
       - name: AWS_SHARED_CREDENTIALS_FILE
         value: /etc/openshift-installer/.awscred
-      - name: AWS_REGION
-        value: us-east-1
       - name: AZURE_AUTH_LOCATION
         value: /etc/openshift-installer/osServicePrincipal.json
-      - name: AZURE_REGION
-        value: centralus
       - name: GOOGLE_CLOUD_KEYFILE_JSON
         value: /etc/openshift-installer/gce.json
       - name: KUBECONFIG

ci-operator/templates/openshift/installer/cluster-launch-installer-src.yaml

@@ -453,12 +453,8 @@ objects:
         value: ${CLUSTER_TYPE}
       - name: AWS_SHARED_CREDENTIALS_FILE
         value: /etc/openshift-installer/.awscred
-      - name: AWS_REGION
-        value: us-east-1
       - name: AZURE_AUTH_LOCATION
         value: /etc/openshift-installer/osServicePrincipal.json
-      - name: AZURE_REGION
-        value: centralus
       - name: GOOGLE_CLOUD_KEYFILE_JSON
         value: /etc/openshift-installer/gce.json
       - name: KUBECONFIG