Is there a way to clone a deployment other than renaming the deployment and deploying it again through the kubectl?
Unfortunately no. At the time of this writing there is no such a tool that will allow to clone your deployment. So you will have to use the option already mentioned in the question or deploy that using helm chart.
With helm your can pass custom parameters such as --generate-name or edit values.yaml content to quickly deploy similar deployment.
Worth mentioning here is also Velero. A tool for backing up kubernetes resources and persistent volumes.
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