Remove ProxiedInMapValue alias, since it is superceded by MapValue

PiperOrigin-RevId: 866010725

Author: protobuf-github-bot

rust/shared.rs

@@ -29,9 +29,6 @@ pub use crate::codegen_traits::{
 pub use crate::cord::{ProtoBytesCow, ProtoStringCow};
 pub use crate::map::{Map, MapIter, MapKey, MapMut, MapValue, MapView};
 
-// TODO: Remove this alias once we have confirmed there are no incoming references.
-pub use MapValue as ProxiedInMapValue;
-
 pub use crate::optional::Optional;
 pub use crate::proxied::{
     AsMut, AsView, IntoMut, IntoProxied, IntoView, Mut, MutProxied, Proxied, View,