chore: update url in core

Author: devcom33

backend/src/main/java/org/heymouad/focusapp/config/SecurityConfig.java

@@ -56,7 +56,7 @@ public CorsConfigurationSource corsConfigurationSource() {
                 "http://localhost:3000",
                 "http://localhost:4173",
                 "http://localhost:5173",
-                "https://habitflow-wyyu.onrender.com/"
+                "https://habitflow-wyyu.onrender.com"
         ));
         configuration.setAllowCredentials(true);
         configuration.setAllowedMethods(Arrays.asList("GET", "POST", "PUT", "DELETE", "OPTIONS", "PATCH"));