Fix ANSI character output regression on Windows

Fixes #5377

common/terminal/colors.go

@@ -17,6 +17,7 @@ package terminal
 import (
 	"fmt"
 	"os"
+	"runtime"
 	"strings"
 
 	isatty "github.com/mattn/go-isatty"
@@ -31,6 +32,10 @@ const (
 // IsTerminal return true if the file descriptor is terminal and the TERM
 // environment variable isn't a dumb one.
 func IsTerminal(f *os.File) bool {
+	if runtime.GOOS == "windows" {
+		return false
+	}
+
 	fd := f.Fd()
 	return os.Getenv("TERM") != "dumb" && (isatty.IsTerminal(fd) || isatty.IsCygwinTerminal(fd))
 }