go.mod: update logrus to v1.8.1

Newer versions contain fixes for recent Go versions, and this removes
the dependency on github.com/konsorten/go-windows-terminal-sequences

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor/github.com/sirupsen/logrus/text_formatter.go

@@ -53,7 +53,10 @@ type TextFormatter struct {
 	// the time passed since beginning of execution.
 	FullTimestamp bool
 
-	// TimestampFormat to use for display when a full timestamp is printed
+	// TimestampFormat to use for display when a full timestamp is printed.
+	// The format to use is the same than for time.Format or time.Parse from the standard
+	// library.
+	// The standard Library already provides a set of predefined format.
 	TimestampFormat string
 
 	// The fields are sorted by default for a consistent output. For applications
@@ -235,6 +238,8 @@ func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []strin
 		levelColor = yellow
 	case ErrorLevel, FatalLevel, PanicLevel:
 		levelColor = red
+	case InfoLevel:
+		levelColor = blue
 	default:
 		levelColor = blue
 	}