Fixes handling of users with a dot in the name when added via config file. #86633 (Mikhail Koviazin).
Fixed the handling of users with a dot in their username when added via the configuration file.
Why it matters
This feature resolves issues encountered when user names containing dots were added through the ClickHouse configuration file, ensuring correct recognition and processing of such users.
How to use it
Add users with dots in their names directly in the user configuration files as usual; the system now correctly processes these user entries without errors.