Update Visual Studio Code settings (#5327)

CONTRIBUTING.md

@@ -30,10 +30,10 @@ ICU4X can be edited using any text editor capable of editing Rust code.
 
 Many ICU4X engineers use [Visual Studio Code](https://code.visualstudio.com/) with the [rust-analyzer](https://marketplace.visualstudio.com/items?itemName=rust-lang.rust-analyzer) extension.
 
-To build all code paths, improve build times in VSCode, and prevent locking the target directory from command-line builds, we recommend the following settings. To add them, choose "Preferences: Open Workspace Settings (JSON)" from the command palette (Ctrl+Shift+P):
+To build all code paths, improve build times in VSCode, and prevent locking the target directory from command-line builds, we recommend the following settings. To add them, choose "Preferences: Open Workspace Settings (JSON)" from the command palette (Ctrl+Shift+P) or (CMD+Shift+P) in mac:
 
 ```json
-"settings": {
+{
 	"rust-analyzer.cargo.features": "all",
 	"rust-analyzer.cargo.extraEnv": {
 		"CARGO_TARGET_DIR": "${workspaceFolder}/target/vscode",