GUACAMOLE-1909: Update the default Max Connections Per User to 0.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/src/main/java/org/apache/guacamole/auth/postgresql/conf/PostgreSQLEnvironment.java

@@ -81,7 +81,7 @@ public class PostgreSQLEnvironment extends JDBCEnvironment {
      * dictate the values that should be used in the absence of the correct
      * properties.
      */
-    private final int DEFAULT_MAX_CONNECTIONS_PER_USER = 1;
+    private final int DEFAULT_MAX_CONNECTIONS_PER_USER = 0;
 
     /**
      * The default value for the default maximum number of connections to be