Updates CHANGELOG.md for windows console unicode

CHANGELOG.md

 ## 1.23.0
 
 ### Core library changes
 * `dart:core`: Added `Uri.isScheme` function to check the scheme of a URI.
    Example: `uri.isScheme("http")`. Ignores case when comparing.
 * `dart:core`: Make `UriData.parse` validate its input better.
   If the data is base-64 encoded, the data is normalized wrt.
   alphabet and padding, and it contains invalid base-64 data,
   parsing fails. Also normalizes non-base-64 data.
 * `dart:io`: Added functions `File.lastAccessed`, `File.lastAccessedSync`,
   `File.setLastModified`, `File.setLastModifiedSync`, `File.setLastAccessed`,
   and `File.setLastAccessedSync`.
 
+### Dart VM
+* Calls to `print()` and `Stdout.write*()` now correctly print unicode
+  characters to the console on Windows. Calls to `Stdout.add*()` behave as
+  before.
+
 ## 1.22.0
 
 ### Language
 
   * Breaking change: ['Generalized tear-offs'](https://github.com/gbracha/generalizedTearOffs/blob/master/proposal.md)
     are no longer supported, and will cause errors. We updated the language spec
     and added warnings in 1.21, and are now taking the last step to fully
     de-support them. They were previously only supported in the VM, and there
     are almost no known uses of them in the wild.
 
@@ skipping 1652 matching lines @@
     they will keep the Dart process alive until they time out. This fixes the
     handling of persistent connections. Previously, the client would shut down
     immediately after a request.
 
   * **Breaking change:** `HttpServer` no longer compresses all traffic by
     default. The new `autoCompress` property can be set to `true` to re-enable
     compression.
 
 * `dart:isolate`: `Isolate.spawnUri` added the optional `packageRoot` argument,
   which controls how it resolves `package:` URIs.