LDAP group sync fails with error "Error": ldap: filter does not start with an '('" on OpenShift Container Platform

Issue

• In order to sync Augmented Active Directory created yml file per example "Example 16. LDAP Sync Configuration Using Augmented Active Directory Schema: augmented_active_directory_config.yaml" in documentation.

[...]
augmentedActiveDirectory:
    groupsQuery:
        baseDN: "ou=groups,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
    groupUIDAttribute: dn 1
    groupNameAttributes: [ cn ] 2
    usersQuery:
        baseDN: "ou=users,dc=example,dc=com"
        scope: sub
        derefAliases: never
        pageSize: 0
[...]

When trying to sync groups it fails.

# oc adm groups sync --sync-config=example-sync.yaml  --confirm
error: validation of LDAP sync config failed: usersQuery.filter: Invalid value: "": invalid query filter: LDAP Result Code 201 "Filter Compile Error": ldap: filter does not start with an '('
See 'oc adm groups sync -h' for help and examples.