Optimise string handling in PeopleRepository filtering.

Jellyfin.Server.Implementations/Item/PeopleRepository.cs

@@ -158,7 +158,8 @@ public class PeopleRepository(IDbContextFactory<JellyfinDbContext> dbProvider, I
 
         if (!string.IsNullOrWhiteSpace(filter.NameContains))
         {
-            query = query.Where(e => e.Name.ToUpper().Contains(filter.NameContains.ToUpper()));
+            var nameContainsUpper = filter.NameContains.ToUpper();
+            query = query.Where(e => e.Name.ToUpper().Contains(nameContainsUpper));
         }
 
         return query;