Set CORS to allow all origins (for now) (#41)

Reviewed-on: #41

backend/main.go

@@ -354,7 +354,9 @@ func start(ctx context.Context, config *ServerConfig) {
 	defer db.db.MustClose()
 
 	router := gin.Default()
-	router.Use(cors.Default())
+	router.Use(cors.New(cors.Config{
+		AllowOrigins: []string{"*"},
+	}))
 	router.GET("/api/users", getUsers)
 	router.GET("/api/user/:userId", getUser)
 	router.POST("/api/user/:userId/allowance", postAllowance)