`ca.crt` is a std field in kubernetes secrets to carry ca bundles. using the standard field allow for better integration with other operators in a supplied consumer fashion.

Currently MTV accepts `cacert` as the field for the ca bundle

For example in my case I am not able to make this flow:
1. ACM creates cluster
2. ManageServiceAccount is created
3. ACM-managed secret is returned with credentials needed by MTV. This secrets has two filed: `token` and ca.cert`
4. returned secret is consumed by MTV provider

I'd like to ask for MTV to be able to accept also ca.crt.