Re-enable rules_jvm_external in downstream
Re-enable rules_jvm_external in downstream

https://github.com/bazelbuild/rules_jvm_external/pull/677 is now merged
bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration,bazelbuild/continuous-integration