Merge pull request #4591 from richm/bug-1465168

Bug 1465168 - mux doesn't recognize ansible boolean parameters correctly

roles/openshift_logging_mux/templates/mux.j2

@@ -102,7 +102,7 @@ spec:
         - name: USE_MUX
           value: "true"
         - name: MUX_ALLOW_EXTERNAL
-          value: "{{ openshift_logging_mux_allow_external | default('false') }}"
+          value: "{{ openshift_logging_mux_allow_external | default('false') | lower }}"
         - name: "BUFFER_QUEUE_LIMIT"
           value: "{{ openshift_logging_mux_buffer_queue_limit }}"
         - name: "BUFFER_SIZE_LIMIT"