Blog about the idea of disconnecting users after DROP USER

MDEV-35617: The proposal is to change behaviour of MariaDB to drop connections of users connected with a dropped user. Blog and ask community feedback.

There are different options here:

• DROP USER kills all active connections
• DROP USER fails "cannot drop, use KILL USER first"
• DROP USER waits until they disconnect (rejecting new connections) — normal DROP behavior.

Perhaps the blog could ask what is preferred?