Deploying GitLab Runners on GCP

I am attempting to use GitLab runners on Google Cloud Platform (GCP). I have been following this guide to get them running on Kubernetes: Tutorial: Configure GitLab Runner to use the Google Kubernetes Engine | GitLab

I get stuck on the fourth step when attempting to use the cert-manager. When I apply it I see the following:

Error from server (BadRequest): error when creating “certificate-issuer-install.yaml”: Namespace in version “v1” cannot be handled as a Namespace: strict decoding error: unknown field “labels”, unknown field “name”
Error from server (BadRequest): error when creating “certificate-issuer-install.yaml”: Certificate in version “v1” cannot be handled as a Certificate: strict decoding error: unknown field “dnsNames”, unknown field “issuerRef”, unknown field “name”, unknown field “namespace”, unknown field “secretName”
Error from server (BadRequest): error when creating “certificate-issuer-install.yaml”: Issuer in version “v1” cannot be handled as a Issuer: strict decoding error: unknown field “name”, unknown field “namespace”, unknown field “selfSigned”

Does anyone know how to fix this?