docs: clarify that the certificate must be in PEM format (#5946)
docs: clarify that the certificate must be in PEM format (#5946)

Signed-off-by: Dax McDonald <4adec569b89398835b18b7edeba28f875f6eb038@users.noreply.github.com>
argoproj/argo-cd,argoproj/argo-cd,argoproj/argo-cd,argoproj/argo-cd,argoproj/argo-cd