chore: bump version to v0.6.4

Update the package version and changelog for the `0.6.4 - 2022-12-15`
release.

CHANGELOG.md

@@ -4,6 +4,17 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## 0.6.4 - 2022-12-15
+
+### Added
+
+- Solidity survey 2022 invitation ([#312](https://github.com/NomicFoundation/hardhat-vscode/issues/312))
+
+### Fixed
+
+- Updated hardhat version to latest, fixing validation for solcjs users ([#305](https://github.com/NomicFoundation/hardhat-vscode/issues/305))
+- Improved foundry import resolution ([#308](https://github.com/NomicFoundation/hardhat-vscode/pull/308))
+
 ## 0.6.3 - 2022-12-01
 
 ### Fixed

package.json

@@ -4,7 +4,7 @@
   "displayName": "Solidity",
   "description": "Solidity and Hardhat support by the Hardhat team",
   "license": "MIT",
-  "version": "0.6.3",
+  "version": "0.6.4",
   "private": true,
   "main": "./client/out/extension.js",
   "module": "./client/out/extension.js",