Group content label for group membership not updated when original entity label changes

@lind101 thanks for your comments. As you mentioned, the group_content label depends on the GroupContentEnabler that manages it.

I have slightly modified the MR code (https://git.drupalcode.org/project/group/-/merge_requests/34/diffs?commi...) so we check that the GroupContentEnabler generated label does not match with the group_content stored label before saving the entity. This mitigates the performance problem when the user did not change the target entity label.

Although we still having a problem if the target entity changes the label and has many group_content entity associated with it. It can take a lot of time to save all the related group_content entities. However, I don't think this is something that can be solved. If you have any idea regarding this, I'll be happy to implement it.

szeidler → changed the visibility of the branch 2767155-2.x to hidden.

There was a problem with the static cache I've fixed in the existing MR using a workaround. However, using a hook_update for maintaining the label of the group_content in sync has an impact on the performance, and seems like a good fit for having a computed value.
I've created a new branch with the new approach. The pending task is to implement a hook_update_N to delete the label column on the database, since is no longer needed.

We've found that the group_content label was not supported by views after changing that field to be a computed field. We've added the views data definition on the GroupContentViewsData class through a new commit.