[client-app] fix hardcoded babelrc path for appveyor
[client-app] fix hardcoded babelrc path for appveyor

nirmit/nylas-mail,simonft/nylas-mail,nylas-mail-lives/nylas-mail,nirmit/nylas-mail,nirmit/nylas-mail,nylas-mail-lives/nylas-mail,nylas/nylas-mail,simonft/nylas-mail,nylas/nylas-mail,nirmit/nylas-mail,simonft/nylas-mail,nylas-mail-lives/nylas-mail,simonft/nylas-mail,nylas-mail-lives/nylas-mail,nylas/nylas-mail,nirmit/nylas-mail,nylas/nylas-mail,simonft/nylas-mail,nylas/nylas-mail,nylas-mail-lives/nylas-mail