cmd/releasebot: shorten code asking for Y/n response

The Y/n prompt code performs just one atomic action.
Reformat its code to be more compact accordingly.

(This will help make the diff of future CLs in stack smaller.)

Change-Id: Iaead279e4529cf627f68c46b914a29226f56463c
Reviewed-on: https://go-review.googlesource.com/c/build/+/382934
Trust: Dmitri Shuralyov <[email protected]>
Run-TryBot: Dmitri Shuralyov <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Carlos Amedee <[email protected]>
Trust: Carlos Amedee <[email protected]>
Auto-Submit: Dmitri Shuralyov <[email protected]>

Author: dmitshur

cmd/releasebot/git.go

@@ -97,15 +97,13 @@ func (w *Work) gitTagVersion() {
 		fmt.Println("dry-run")
 		return
 	}
-	var response string
-	_, err := fmt.Scanln(&response)
-	if err != nil {
+	var resp string
+	if _, err := fmt.Scanln(&resp); err != nil {
 		w.log.Panic(err)
-	}
-	if response != "Y" && response != "y" {
+	} else if resp != "Y" && resp != "y" {
 		w.log.Fatal("stopped as requested")
 	}
-	out, err = r.runErr("git", "tag", w.Version, w.VersionCommit)
+	out, err := r.runErr("git", "tag", w.Version, w.VersionCommit)
 	if err != nil {
 		w.logError("git tag failed: %s\n%s", err, out)
 		return

cmd/releasebot/main.go

@@ -212,12 +212,10 @@ func mailDLCL() {
 		fmt.Println("dry-run")
 		return
 	}
-	var response string
-	_, err := fmt.Scanln(&response)
-	if err != nil {
+	var resp string
+	if _, err := fmt.Scanln(&resp); err != nil {
 		log.Fatalln(err)
-	}
-	if response != "Y" && response != "y" {
+	} else if resp != "Y" && resp != "y" {
 		log.Fatalln("stopped as requested")
 	}
 	changeURL, err := task.MailDLCL(context.Background(), versions)
@@ -268,12 +266,10 @@ func postTweet(kind string) {
 		fmt.Printf("and with the following announcement URL:\n\n\t%s\n\n", tweet.Announcement)
 	}
 	fmt.Print("Ok? (Y/n) ")
-	var response string
-	_, err = fmt.Scanln(&response)
-	if err != nil {
+	var resp string
+	if _, err = fmt.Scanln(&resp); err != nil {
 		log.Fatalln(err)
-	}
-	if response != "Y" && response != "y" {
+	} else if resp != "Y" && resp != "y" {
 		log.Fatalln("stopped as requested")
 	}
 	tweetRelease := map[string]func(workflow.TaskContext, task.ReleaseTweet, bool) (string, error){