Singletons => Change method to make singleton class

ExpressAPI/src/config/Config.ts

ExpressAPI/src/helpers/DojoValidators.ts

ExpressAPI/src/managers/GitlabManager.ts

ExpressAPI/src/managers/HttpManager.ts

ExpressAPI/src/managers/UserManager.ts

ExpressAPI/src/middlewares/ParamsCallbackManager.ts

ExpressAPI/src/middlewares/ParamsValidatorMiddleware.ts

ExpressAPI/src/middlewares/SecurityMiddleware.ts

ExpressAPI/src/middlewares/SessionMiddleware.ts

ExpressAPI/src/routes/ApiRoutesManager.ts

ExpressAPI/src/routes/BaseRoutes.ts

ExpressAPI/src/routes/EnonceRoutes.ts

ExpressAPI/src/routes/ExerciceRoutes.ts

ExpressAPI/src/routes/GitlabRoutes.ts

ExpressAPI/src/routes/SessionRoutes.ts

ExpressAPI/src/shared