metadata of typescript DevWorkspace types is just object

[sleshchenko]

Describe the bug
metadata of typescript DevWorkspace types is just object, but for clients it's needed to know that it has all fields from K8s API, like namespace, name, annotations https://github.com/devfile/api/blob/main/pkg/apis/workspaces/v1alpha2/devworkspace_types.go#L80

To Reproduce
Steps to reproduce the behavior:

1. Import devfile/api somewhere in typescript project.
2. Check V1alpha2DevWorkspace or V1alpha2DevWorkspaceTempalate. Metadata there is just an object

Expected behavior
it's expected it has all field from K8s ObjectMeta.

[sleshchenko]

related controller-gen PR kubernetes-sigs/controller-tools#557.
metadata can have limited number of fields: name, namespace, labels, annotations and finalizers
Added in #524.