Update changelog

Author: DustinCampbell

CHANGELOG.md

@@ -9,6 +9,7 @@
 #### Completion List
 
 * No longer trigger completion when a '<' character is typed. ([#1521](https://github.com/OmniSharp/omnisharp-vscode/issues/1521), PR: [#1530](https://github.com/OmniSharp/omnisharp-vscode/pull/1530))
+* Completion list no longer triggers on space in contexts where a lambda expression could be typed. ([#1524](https://github.com/OmniSharp/omnisharp-vscode/issues/1524), PR: [#1548](https://github.com/OmniSharp/omnisharp-vscode/pull/1548))
 
 #### Other Updates and Fixes