fix: removed colorization on non-tty

Fixes a bug whereby `cheat` would apply ANSI colorization even when
outputting into a non-TTY.

vendor/github.com/mattn/go-isatty/isatty_bsd.go

@@ -16,3 +16,9 @@ func IsTerminal(fd uintptr) bool {
 	_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, fd, ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
 	return err == 0
 }
+
+// IsCygwinTerminal return true if the file descriptor is a cygwin or msys2
+// terminal. This is also always false on this environment.
+func IsCygwinTerminal(fd uintptr) bool {
+	return false
+}