Update download.md: remove legacy os license link

site/download.md

@@ -71,13 +71,6 @@ type.
 Download links for some further old versions are available on the
 [Version History](/changelog) page.
 
-### License key for legacy macOS
-
-You may use the following license key to unlock PopClip for free on any macOS version before 10.15:
-[Download License Key](https://api.pilotmoon.com/v2/licenseKeys/lk_iimPQ62Egziy/file?token=354IB4K45TwF1cLppgYdXKFOVQIq49GtyYxw4YAjIe86DD9ZpgMbKTh)
-
-(Install and run PopClip first, then save the `.popcliplicense` file and double-click it.)
-
 ## Beta Release
 
 See [Beta](/beta).