Migrate drone and minio instance to sfosc.org domain

[Beanow]

Currently I'm sponsoring a drone and minio instance to update the sourcecred prototype from.
The domain I used for these things though is *.sfosc.robin-it.com.

Which might look like a corporate sponsorship, because I use this for my freelance site as well. Actual reason for using it was because other domain names I own are just silly or ugly.

Migrating it to be *.sfosc.org makes more sense to me. The changes would include some DNS changes, updating the badge links, the drone config reference to minio and reconnecting drone to GitHub (as the webhook address would be different).