Only set shell: true on Windows

Author: smashwilson

script/helpers/run-atom.js

@@ -3,14 +3,15 @@ const {spawn} = require('child_process');
 function atomProcess(env, ...args) {
   const atomBinPath = process.env.ATOM_SCRIPT_PATH || 'atom';
   const atomEnv = {...process.env, ...env};
+  const isWindows = process.platform === 'win32';
 
   return new Promise((resolve, reject) => {
     let settled = false;
 
     const child = spawn(atomBinPath, args, {
       env: atomEnv,
       stdio: 'inherit',
-      shell: true,
+      shell: isWindows,
       windowsHide: true,
     });