Merge pull request #1016 from Bilb/test-use-pkill-rather-killall

[test] use pkill instead of killall for running test windows

integration_test/common.js

@@ -98,7 +98,7 @@ module.exports = {
     const killStr =
       process.platform === 'win32'
         ? 'taskkill /im electron.exe /t /f'
-        : 'killall -9 electron';
+        : 'pkill -f "node_modules/.bin/electron"';
     return new Promise(resolve => {
       exec(killStr, (err, stdout, stderr) => {
         if (err) {