cmd/clef: fix staticcheck warnings (ethereum#20314)

cmd/clef/main.go

@@ -387,7 +387,7 @@ func initialize(c *cli.Context) error {
 	if c.GlobalBool(stdiouiFlag.Name) {
 		logOutput = os.Stderr
 		// If using the stdioui, we can't do the 'confirm'-flow
-		fmt.Fprintf(logOutput, legalWarning)
+		fmt.Fprint(logOutput, legalWarning)
 	} else {
 		if !confirm(legalWarning) {
 			return fmt.Errorf("aborted by user")
@@ -579,7 +579,7 @@ func signer(c *cli.Context) error {
 		},
 	})
 
-	abortChan := make(chan os.Signal)
+	abortChan := make(chan os.Signal, 1)
 	signal.Notify(abortChan, os.Interrupt)
 
 	sig := <-abortChan
@@ -694,7 +694,7 @@ func checkFile(filename string) error {
 
 // confirm displays a text and asks for user confirmation
 func confirm(text string) bool {
-	fmt.Printf(text)
+	fmt.Print(text)
 	fmt.Printf("\nEnter 'ok' to proceed:\n> ")
 
 	text, err := bufio.NewReader(os.Stdin).ReadString('\n')