Bump default PostgreSQL version to 16 (#3797)

Closes #3798

Author: roji

src/EFCore.PG/Infrastructure/Internal/NpgsqlOptionsExtension.cs

@@ -36,7 +36,7 @@ public override ParameterTranslationMode ParameterizedCollectionMode
     ///     any release. You should only use it directly in your code with extreme caution and knowing that
     ///     doing so can result in application failures when updating to a new Entity Framework Core release.
     /// </summary>
-    public static readonly Version DefaultPostgresVersion = new(14, 0);
+    public static readonly Version DefaultPostgresVersion = new(16, 0);
 
     /// <summary>
     ///     The backend version to target.