[Shadows] Annotate "to be deprecated" symbols for MDCShadowLayer.
[Shadows] Annotate "to be deprecated" symbols for MDCShadowLayer.

PiperOrigin-RevId: 457552881

material-components/material-components-ios,material-components/material-components-ios,material-components/material-components-ios,material-components/material-components-ios,material-components/material-components-ios