Update import name guidelines to use 'SHOULD' for intermediate names

Author: brettcannon

source/specifications/core-metadata.rst

@@ -745,7 +745,7 @@ the project.
 
 Projects SHOULD list all the shortest import names that are exclusively provided
 by the project. If any of the shortest names are dotted names, all intervening
-names from that name to the top-level name should also be listed appropriately
+names from that name to the top-level name SHOULD also be listed appropriately
 in ``Import-Name`` and/or ``Import-Namespace``.
 
 If a project lists the same name in both ``Import-Name`` and
@@ -800,7 +800,7 @@ project.
 
 Projects SHOULD list all the shortest import names that are exclusively provided
 by the project. If any of the shortest names are dotted names, all intervening
-names from that name to the top-level name should also be listed appropriately
+names from that name to the top-level name SHOULD also be listed appropriately
 in ``Import-Name`` and/or ``Import-Namespace``.
 
 The import names listed in this field MUST be importable when the project is