Update explicit-tracking.md (#3128)

Add missing word

Author: mrlife

entity-framework/core/change-tracking/explicit-tracking.md

@@ -19,7 +19,7 @@ Entity Framework Core (EF Core) change tracking works best when the same <xref:M
 > You can run and debug into all the code in this document by [downloading the sample code from GitHub](https://github.com/dotnet/EntityFramework.Docs/tree/master/samples/core/ChangeTracking/ChangeTrackingInEFCore).
 
 > [!TIP]
-> For simplicity, this document uses and references synchronous methods such as <xref:Microsoft.EntityFrameworkCore.DbContext.SaveChanges%2A> rather their async equivalents such as <xref:Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync%2A>. Calling and awaiting the async method can be substituted unless otherwise noted.
+> For simplicity, this document uses and references synchronous methods such as <xref:Microsoft.EntityFrameworkCore.DbContext.SaveChanges%2A> rather than their async equivalents such as <xref:Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync%2A>. Calling and awaiting the async method can be substituted unless otherwise noted.
 
 ## Introduction