Don't mention current ResolveVersion in comment

Author: weihanglo

src/cargo/core/resolver/resolve.rs

@@ -46,8 +46,10 @@ pub struct Resolve {
     summaries: HashMap<PackageId, Summary>,
 }
 
-/// A version to indicate how a `Cargo.lock` should be serialized. Currently
-/// [V3 is the default](ResolveVersion::default) when creating a new lockfile.
+/// A version to indicate how a `Cargo.lock` should be serialized.
+///
+/// When creating a new lockfile, the default version defined in
+/// [`ResolveVersion::default`] is used.
 /// If an old version of lockfile already exists, it will stay as-is.
 ///
 /// It's theorized that we can add more here over time to track larger changes