Clean up tests

lib/install.js

@@ -2,8 +2,11 @@
 
 const bin = require('.');
 
-bin.run(['version']).then(() => {
-  console.log('✔ Hugo installed successfully!');
-}).catch(error => {
-  console.error('✖ ERROR: Hugo installation failed. :(\n', error);
-});
+(async () => {
+  try {
+    await bin.run(['version']);
+    console.log('✔ Hugo installed successfully!');
+  } catch (error) {
+    console.error('✖ ERROR: Hugo installation failed. :(\n', error);
+  }
+})();