Validate output of `make generate` in a presubmit to make sure it is run

Add a presubmit to validate output of `make generate` when creating the generated code in the `api` package. Right now, we just have a suggestion to remind the user to do this manually, but adding a presubmit ensures that code won't get merged unless this target is run.

https://github.com/aws/eks-anywhere/blob/f454a4acff5c1daf7246bd2ac379c5d2c6cfa4a9/pkg/api/v1alpha1/tinkerbelldatacenterconfig_types.go#L11

https://github.com/aws/eks-anywhere/blob/f5a58040f7a35f56806c8840f71cc788d8292d52/Makefile#L363-L364

Start with the linked Makefile lines 363-364 and the generated file pkg/api/v1alpha1/tinkerbelldatacenterconfig_types.go to understand the existing make generate target and reminder. Then find the repository's presubmit configuration and make it validate that generated output is up to date; done means presubmit fails when generation is skipped and passes after make generate.

Written by the indexing model from the issue text.