Update Changelog (#200)

* docs: update changelog

* docs: update changelog

Author: HamdaanAliQuatil

CHANGELOG.md

@@ -1,5 +1,7 @@
 # 0.6.0
 * Replaced the `KeyPair` class with `typedef KeyPair<T, S> = ({T privateKey, S publicKey})` and refactored key generation methods to return a named record.
+* Bumped minimum required CMake version to `3.10` for building the
+  bundled native library (`flutter pub run webcrypto:setup`).
 
 # 0.5.8
 * All classes previously annotated `@sealed` are now `final`!