chore: fix nit for import organization

This will be caught automatically when we add import linting
(#442)

Author: kumar303

src/program.js

@@ -1,6 +1,8 @@
 /* @flow */
 import path from 'path';
 import {readFileSync} from 'fs';
+
+import git from 'git-rev-sync';
 import yargs from 'yargs';
 
 import defaultCommands from './cmd';
@@ -10,8 +12,6 @@ import {createLogger, consoleStream as defaultLogStream} from './util/logger';
 const log = createLogger(__filename);
 const envPrefix = 'WEB_EXT';
 
-import git from 'git-rev-sync';
-
 
 /*
  * The command line program.