Follow-up from "Add NuGet package tags support"

The following discussion from !30726 (merged) should be addressed:

• @mayra-cabrera started a discussion: (+5 comments)

  Do we know an average of how many tags are going to insert? Should we ensure that are less than the TAGS_LIMIT?

Rename Packages::Tag::TAGS_LIMIT constant to something more readable so that new readers can get that this constant is specific to the Packages::Tag.for_packages scope.

Optional: Do a deeper analysis. If I recall correctly, I put the max_tags_limit parameter in the Packages::Tag.for_packages scope to be able to test the scope with a reduced limit. There might be an alternative to this and the max_tags_limit parameter could be removed.