MDEV-37776: connect engine Debian packaging shouldn't depend explictly on libxml2

The dependency on libxml2 will be populated by its shlibs:Depends
directive.

Thanks Simon Chopin for pointing out the error of our ways.

ref: https://bugs.launchpad.net/ubuntu/+source/libxml2/+bug/2125555

Author: grooverdan

debian/control

@@ -803,8 +803,7 @@ Description: Backup tool for MariaDB server
 
 Package: mariadb-plugin-connect
 Architecture: any
-Depends: libxml2,
-         mariadb-server (= ${server:Version}),
+Depends: mariadb-server (= ${server:Version}),
          unixodbc,
          ${misc:Depends},
          ${shlibs:Depends}