Use previous minor version not previous security minor version for "previous minor" variant
Problem/Motivation
Right now, Drupal 10.2.x is at 10.2.7, but the latest security update was 10.2.2. Sometimes, some changes are backported to the latest 10.2.x, like this one https://www.drupal.org/node/3437129, but that's only available in 10.2.7
So, this type of situation just brings the question of "do we need the 'previous minor' variant to be the security one?
Probably the concept of “security” releases is not as important for previous minor, unless you think of it like a LTS sort of thing (ie: people might not update until there is a new “security” release).
Proposed resolution
Maybe we could have a simpler CORE_PREVIOUS_MINOR that just has the latest previous minor. We can still keep the old variable in case people reference it, but not use it in the templates.
Note that there is a good deal of logic in the "scripts/check_versions.php" script that would need to be modified.
Remaining tasks
It could be a fix or won't fix, but creating the issue to at least discuss it.