[pkg] Add missing entries to MANIFEST.in Detected by running `check-manifest <https://github.com/mgedmin/check-manifest>`_. Add a tox environment accordingly. Closes #15229018.

if 'same_as' in schema:
    sync_schema_props_perms('same_as', syncperms=False)
sync_schema_props_perms('Bookmark', syncperms=False)