internal/https: remove redundant Close in ListenAndServe

This was missed in CL 159701.

Change-Id: Ieffdc2575086b67965d5bef4d0253d644ba34936
Reviewed-on: https://go-review.googlesource.com/c/build/+/205677
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/internal/https/https.go b/internal/https/https.go
index d9305da..45cef37 100644
--- a/internal/https/https.go
+++ b/internal/https/https.go
@@ -51,13 +51,11 @@
 
 	if opt.AutocertCacheBucket == "" {
 		err := http.Serve(ln, handler)
-		ln.Close()
 		return fmt.Errorf("http.Serve = %v", err)
 	}
 
 	// handler is served primarily via HTTPS, so just redirect HTTP to HTTPS.
 	redirect := &http.Server{
-		Addr:    ln.Addr().String(),
 		Handler: http.HandlerFunc(redirectToHTTPS),
 	}
 	errc := make(chan error)
@@ -105,10 +103,7 @@
 	defer ln.Close()
 
 	ctx, cancel := context.WithCancel(ctx)
-	server := &http.Server{
-		Addr:    ln.Addr().String(),
-		Handler: h,
-	}
+	server := &http.Server{Handler: h}
 	done := make(chan struct{})
 	go func() {
 		<-ctx.Done()