add changelog

Author: anthony-gomez-fastly

CHANGELOG.md

@@ -10,6 +10,8 @@
   [#1419](https://github.com/fastly/cli/pull/1419)
 - breaking(language.rust): Switch Rust builds to wasm32-wasip1 instead of wasm32-wasi [#1382](https://github.com/fastly/cli/pull/1382)
 
+- breaking(build): Remove assemblyscript [#1001](https://github.com/fastly/cli/pull/1001/files)
+
 **Enhancements:**
 
 - fix(compute/init): Updates for renamed TypeScript default starter kit