attempt-backport: git reset before updating

Author: Fishrock123

scripts/attempt-backport.js

@@ -152,10 +152,15 @@ function attemptBackport (options, version, isLTS, cb) {
         debug(`error before exit, code: ${code}, on '${argsString}'`)
         return
       }
-      gitRemoteUpdate()
+      gitResetBefore()
     })
   }
 
+  function gitResetBefore () {
+    options.logger.debug(`resetting origin/v${version}.x-staging...`)
+    wrapCP('git', ['reset', `origin/v${version}.x-staging`, '--hard'], gitRemoteUpdate)
+  }
+
   function gitRemoteUpdate () {
     options.logger.debug('updating git remotes...')
     wrapCP('git', ['remote', 'update', '-p'], gitCheckout)