Fix uninstall script to hardcode extension ID

Author: j-256

package.json

@@ -46,7 +46,7 @@
     "package": "vsce package --allow-star-activation",
     "publish": "vsce publish --allow-star-activation",
     "reinstall": "rm -f *.vsix && npm run package && code --install-extension git-crypt-vscode-*.vsix && rm -f *.vsix",
-    "uninstall": "code --uninstall-extension $npm_package_publisher.$npm_package_name"
+    "uninstall": "code --uninstall-extension j-256.git-crypt-vscode"
   },
   "devDependencies": {
     "@types/vscode": "^1.85.0",