Admin manual: Fix another typo and missing value

- "skip_server_name" with underscores.
- Add "= 1" which was missing. Assuming that the previous author meant
  to enable this, since the default is 0.

Signed-off-by: Simon Westersund <swestersund@users.noreply.github.com>

admin_manual/configuration_database/linux_database_configuration.rst

@@ -58,7 +58,7 @@ Your :file:`/etc/mysql/my.cnf` could look like this:
 ::
 
   [server]
-  skip-name-resolve
+  skip_name_resolve = 1
   innodb_buffer_pool_size = 128M
   innodb_buffer_pool_instances = 1
   innodb_flush_log_at_trx_commit = 2