bug(mat-date-picker): the native date adapter can't detect first day of week from user locale

#### Reproduction

All material datepickers display weeks starting Sunday while I have Russia locale set up which demands Monday is the first day of week:

Yes, I know I can globally change starting day via DateAdapter but I need to datepickers to be users' locale compatible.

#### Expected Behavior
Monday is first day of week

#### Actual Behavior

Sunday is first day of week.

#### Environment

- Angular: 11.0.3
- CDK/Material: 11.2.4
- Browser(s): Firefox 89
- Operating System (e.g. Windows, macOS, Ubuntu): macOS 11.4

Empieza reproduciendo el problema con Angular Material datepickers y una Russia locale; después, inspecciona el native date adapter y cómo gestiona su locale. Se considera terminado cuando el datepicker muestra Monday como el primer día de la semana para esa locale, manteniendo el comportamiento existente de global DateAdapter override.

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