Revert "LPS-50155 Ensure that store() does not save strict portlet preferences to the DB"

This reverts commit 92447575c47bfb9c405ac66545d0c5ba80f24909.
Revert "LPS-50155 Avoid strict portlet preferences being created as empty during import"

This reverts commit 8f9e66c2c0c9fb85793d8638dadee9c01b1a8eef.