Observed inconsistency between Project and Namespace. Label added for the project when entered empty string. However the label or annotate with a string value to a Namespace or project doesn't work.

1. Create a project : `$ oc create namespace testproject`
2. Assign admin access to user : `$ oc adm policy add-role-to-user admin testuser -n testproject`
3. Login with the user : `$ oc login -u testuser`
4. Label ns : `$ oc label ns testproject test1=label1`
5. Annotate ns : `$ oc annotate ns testproject openshift.io/node-selector=test2=test2`
6. Label project : `$ oc label project testproject test1=label1` 
7. Annotate project : `$ oc annotate project testproject openshift.io/node-selector=test2=test2`
8. Label project (this specific label worked): `$ oc label project testproject policy-group.network.openshift.io/ingress=""`

When a new label with non-empty string is added to a project, validation error will occur . And when a new label with empty string is added to a project, the project is labeled :
~~~
$ oc label project testproject policy-group.network.openshift.io/ingress=""` project.project.openshift.io/testproject labeled
~~~

The project Admin does not have access to modify the project/namespace resource itself.

Label ns : `$ oc label ns testproject test1=label1`
~~~
Error from server (Forbidden): namespaces "testproject" is forbidden: User "testuser" cannot patch resource "namespaces" in API group "" in the namespace "testproject"
~~~
Annotate ns : `$ oc annotate ns testproject openshift.io/node-selector=test2=test2`
~~~
Error from server (Forbidden): namespaces "testproject" is forbidden: User "testuser" cannot patch resource "namespaces" in API group "" in the namespace "testproject"
~~~

Label project : `$ oc label project testproject test1=label1`
~~~
The Project "testproject" is invalid: metadata.labels[test1]: Invalid value: "label1": field is immutable, , try updating the namespace
~~~ 
Annotate project : `$ oc annotate project testproject openshift.io/node-selector=test2=test2`
~~~   
The Project "testproject" is invalid: metadata.annotations[openshift.io/node-selector]: Invalid value: "test2=test2": field is immutable, try updating the namespace 
~~~

However when tried with empty string : It worked :
~~~
$ oc label project testproject policy-group.network.openshift.io/ingress=""
project.project.openshift.io/testproject labeled
~~~