Running and inspecting sanity of deployments on Kubernetes
Kubernetes does not provide this by default and to accomplish it you will need to use external tools to ensure the desired configuration is applied, monitoring and enforcing it.
That is a wide discussion, and everithing will depends of how your cluster is configured, how you allow the access to your cluster etc...
But, It is common to use some CI/CD pipeline to apply the configuration times to times, or when you need to alter something.
You can also use the kubernetes auditing to verify what happened in your cluster and maybe create some alert or actions to trigger a re-apply of your resources.