chore(deps): update dependency io.vertx:vertx-core to v3.9.0 (#2522)
chore(deps): update dependency io.vertx:vertx-core to v3.9.0 (#2522)


GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples,GoogleCloudPlatform/java-docs-samples