Fix link

Author: cimnine

README.md

@@ -21,7 +21,7 @@ Do you have any questions? Before opening an issue on Github, please join the [N
 [netbox-docker-github]: https://github.com/netbox-community/netbox-docker/
 [ntc-slack]: http://slack.networktocode.com/
 [netbox-docker-slack]: https://slack.com/app_redirect?channel=netbox-docker&team=T09LQ7E9E
-[netbox-docker-license]: https://github.com/netbox-community/netbox-docker/blob/master/LICENSE
+[netbox-docker-license]: https://github.com/netbox-community/netbox-docker/blob/release/LICENSE
 
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