Remove ignore that is no longer needed

Author: mikewiebe

tests/sanity/ignore-2.15.txt

@@ -18,6 +18,5 @@ plugins/modules/dcnm_vpc_pair.py validate-modules:missing-gplv3-license # GPLv3
 plugins/modules/dcnm_fabric.py validate-modules:missing-gplv3-license # GPLv3 license header not found in the first 20 lines of the module
 plugins/modules/dcnm_maintenance_mode.py validate-modules:missing-gplv3-license # GPLv3 license header not found in the first 20 lines of the module
 plugins/modules/dcnm_bootflash.py validate-modules:missing-gplv3-license # GPLv3 license header not found in the first 20 lines of the module
-plugins/modules/dcnm_rest.py import-2.7!skip
 plugins/httpapi/dcnm.py import-3.9!skip
 plugins/httpapi/dcnm.py import-3.10!skip