doc for string methods using char agrs

Author: maumar

entity-framework/core/what-is-new/ef-core-10.0/whatsnew.md

@@ -84,7 +84,8 @@ See [#12793](https://github.com/dotnet/efcore/issues/12793) and [#35367](https:/
 - Optimization for `MIN`/`MAX` over `DISTINCT` ([#34699](https://github.com/dotnet/efcore/pull/34699), contributed by [@ranma42](https://github.com/ranma42)).
 - Translation for date/time functions using `DatePart.Microsecond` and `DatePart.Nanosecond` arguments ([#34861](https://github.com/dotnet/efcore/pull/34861)).
 - Simplifying parameter names (e.g. from `@__city_0` to `city`) ([#35200](https://github.com/dotnet/efcore/pull/35200)).
-- Translate `COALESCE` as `ISNULL` ([#34171](https://github.com/dotnet/efcore/pull/34171), contributed by [@ranma42](https://github.com/ranma42)).
+- Translate `COALESCE` as `ISNULL` on SQL Server, for most cases ([#34171](https://github.com/dotnet/efcore/pull/34171), contributed by [@ranma42](https://github.com/ranma42)).
+- Support for some string functions taking `char` as arguments ([#34999](https://github.com/dotnet/efcore/pull/34999), contributed by [@ChrisJollyAU](https://github.com/ChrisJollyAU)).
 
 ## ExecuteUpdateAsync now accepts a regular, non-expression lambda