Remove bad sanity ignore entry.

test/sanity/ignore.txt

@@ -1607,7 +1607,6 @@ lib/ansible/modules/cloud/openstack/os_keypair.py validate-modules:doc-missing-t
 lib/ansible/modules/cloud/openstack/os_keystone_domain.py validate-modules:doc-missing-type
 lib/ansible/modules/cloud/openstack/os_keystone_domain_info.py validate-modules:parameter-type-not-in-doc
 lib/ansible/modules/cloud/openstack/os_keystone_domain_info.py validate-modules:doc-missing-type
-lib/ansible/modules/cloud/openstack/os_keystone_endpoint.py validate-modules:option-incorrect-version-added
 lib/ansible/modules/cloud/openstack/os_keystone_endpoint.py validate-modules:undocumented-parameter
 lib/ansible/modules/cloud/openstack/os_keystone_endpoint.py validate-modules:parameter-type-not-in-doc
 lib/ansible/modules/cloud/openstack/os_keystone_endpoint.py validate-modules:doc-missing-type