Do Articles 8, 10 and 157 of the Treaty on the Functioning of the European Union, Article 3 of the Treaty on European Union, Article 23 and Article 33(2) of the Charter of Fundamental Rights, and Article 1 and Article 14(1) of Directive 2006/54, all taken in conjunction with Directive 2010/18 implementing the Framework Agreement on parental leave, preclude a rule of national law such as Article 37(6) of the Workers’ Statute, which makes it a requirement that in order to exercise the right to reconcile family life and working life so as to be able to care directly for children or family members for whom they are responsible, workers must in all cases reduce their ordinary working hours, with a consequent proportional reduction in salary?