Add opencensus-exporter-trace-zipkin to list of artifacts to release. (#733)
Add opencensus-exporter-trace-zipkin to list of artifacts to release. (#733)


sebright/instrumentation-java,census-instrumentation/opencensus-java,bogdandrutu/opencensus-java,bogdandrutu/instrumentation-java,census-instrumentation/opencensus-java,songy23/instrumentation-java,census-instrumentation/opencensus-java,songy23/instrumentation-java,sebright/opencensus-java,sebright/opencensus-java,sebright/instrumentation-java,bogdandrutu/instrumentation-java,songy23/instrumentation-java,sebright/opencensus-java,bogdandrutu/opencensus-java,bogdandrutu/opencensus-java