Bumping central dashboard node version to v12.18.3 (#5016)
Bumping central dashboard node version to v12.18.3 (#5016)

When building current master branch central dashboard on arm64,
error message `Segmentation fault (core dumped)` will occur. By
bumping base image node version to 12.18.3, this error can be fixed.

Signed-off-by: Henry Wang <a41ab0e52665860c6a81797bfeb8280a2336aa1a@arm.com>
kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow,kubeflow/kubeflow