Update CHANGELOG for v2.3.0-preview.4

Author: andyleejordan

CHANGELOG.md

@@ -1,5 +1,15 @@
 # PowerShell Editor Services Release History
 
+## v2.3.0-preview.4
+### Tuesday, February 23, 2021
+
+- [PowerShellEditorServices #1416](https://github.com/PowerShell/PowerShellEditorServices/pull/1416) -
+  Fix some markdownlint errors in README.
+- [PowerShellEditorServices #1415](https://github.com/PowerShell/PowerShellEditorServices/pull/1415) -
+  Fix configuration processing to ensure that profiles are loaded.
+- [PowerShellEditorServices #1415](https://github.com/PowerShell/PowerShellEditorServices) -
+  Merge pull request #1414 from andschwa/changelog-v2021.2.0.
+
 ## v2.3.0-preview.3
 ### Friday, February 19, 2021