Description of problem:

Responses from the registry "ListBundles" endpoint report {"properties":[{}],...} or {"dependencies":[{}]}, respectively, when a given bundle has no stored properties or dependencies.

Backwards compatibility for bundles that do not specify provided and required GVKs using properties and dependencies is not activated when a bundle reports at least one property or dependency (https://github.com/operator-framework/operator-lifecycle-manager/blob/master/pkg/controller/registry/resolver/operators.go#L259-L273), so dependency resolutions will not recognize the provided or required APIs for older bundles.

Version-Release number of selected component (if applicable):

4.6.0

How reproducible: always

Steps to Reproduce:
1. Extract the database from an image:

$ docker cp $(docker create quay.io/operator-framework/upstream-community-operators):/bundles.db .

2. Serve with opm:

$ opm registry serve -d bundles.db

2. Query the ListBundles endpoint:

$ grpcurl --plaintext localhost:50051 api.Registry/ListBundles | jq '{csvName,dependencies,properties}|select(.properties==[{}] or .dependencies==[{}])'

Actual results:

Many bundles in the response show [{}] for either properties or dependencies.


...
{
  "csvName": "infinispan-operator.v1.0.1",
  "dependencies": [
    {}
  ],
  "properties": [
    {
      "type": "olm.gvk",
      "value": "{\"group\":\"infinispan.org\",\"kind\":\"Infinispan\",\"version\":\"v1\"}"
    },
    {
      "type": "olm.package",
      "value": "{\"packageName\":\"infinispan\",\"version\":\"1.0.1\"}"
    }
  ]
}
...

Expected results:

No bundles in the response should have an empty entry -- {} -- in their dependencies or properties fields. Instead, those fields should be omitted, null, or [].