generate bundle: Support overwriting of annotations.yaml

[adambkaplan]

Feature Request

Describe the problem you need a feature to resolve.

Operator bundles need to have annotations for releasing in various catalogs. These should be synced between bundle.Dockerfile and annotations.yaml, per the bundle format docs. However, operator-sdk generate bundle provides no easy means to do this. --overwrite wipes out any additional labels on the bundle.Dockerfile.

Describe the solution you'd like.

Amend --overwrite to support overwriting annotations only (or provide a new --overwrite-annotations option). Ex:

operator-sdk generate bundle --overwrite=annotations

/language go