Ensure Windows builds work if the username contains spaces

Without this, we hit issues where the path to the server contains
spaces, and that means this fails to run successfully. With this
change, the paths on Windows are quoted, which avoids that issue.

Author: pimterry

src/index.ts

@@ -173,8 +173,9 @@ function showNotification(title: string, body: string) {
 async function startServer(retries = 2) {
     const binName = isWindows ? 'httptoolkit-server.cmd' : 'httptoolkit-server';
     const serverBinPath = path.join(__dirname, '..', 'httptoolkit-server', 'bin', binName);
+    const serverBinCommand = isWindows ? `"${serverBinPath}"` : serverBinPath;
 
-    server = spawn(serverBinPath, ['start'], {
+    server = spawn(serverBinCommand, ['start'], {
         windowsHide: true,
         stdio: ['inherit', 'pipe', 'pipe'],
         shell: isWindows, // Required to spawn a .cmd script