Fix broken test

Trying to test the actual terminal output doesn't always work
across different platforms.

Author: aaronvb

pkg/renderer/printer_log.go

@@ -17,5 +17,5 @@ func (pl *PrinterLog) Write(b []byte) (n int, err error) {
 	str := pl.Prefix.WithShowLineNumber(false).Sprint(string(b))
 	pterm.Println(str)
 
-	return len(str), nil
+	return len(b), nil
 }

pkg/renderer/printer_log_test.go

@@ -6,26 +6,14 @@ import (
 	"github.com/pterm/pterm"
 )
 
-func TestWriteDefaultPrefix(t *testing.T) {
+func TestWrite(t *testing.T) {
 	pterm.DisableOutput()
 
 	pl := PrinterLog{}
 	b := []byte("foobar")
 	i, _ := pl.Write(b)
 
-	if i != 34 {
-		t.Errorf("Expected str len %d, got %d", 34, i)
-	}
-}
-
-func TestWriteErrorPrefix(t *testing.T) {
-	pterm.DisableOutput()
-
-	pl := PrinterLog{Prefix: pterm.Error}
-	b := []byte("foobar")
-	i, _ := pl.Write(b)
-
-	if i != 38 {
-		t.Errorf("Expected str len %d, got %d", 38, i)
+	if i != len(b) {
+		t.Errorf("Expected str len %d, got %d", len(b), i)
 	}
 }