Update changelog for 527 and 531

Author: axelson

CHANGELOG.md

@@ -3,6 +3,12 @@
 Improvements:
 - Add commands for piping and unpiping text (thanks [Paulo Valente](https://github.com/polvalente)) [#515](https://github.com/elixir-lsp/elixir-ls/pull/515)
 
+Bug Fixes:
+- Fix suggest contracts windows regression (thanks [Łukasz Samson](https://github.com/lukaszsamson)) [#531](https://github.com/elixir-lsp/elixir-ls/pull/531)
+
+Housekeeping:
+- Minor iteration/performance improvements (thanks [Andrew Summers](https://github.com/asummers)) [#527](https://github.com/elixir-lsp/elixir-ls/pull/527)
+
 ### v0.7.0: 06 April 2021
 
 Improvements: