OBS is the OpenSUSE Build Service. It automates package creation from source code.
You may want to revisit the article you linked to, because I just used it to fix the exact same situation you are reporting.
You also have a typo in your repo creation echo statement above. You have a space and a forward slash outside of the first set of double quotes that should be within them. That wouldn’t cause your error, though, so I encourage dumping your old repo and keyring files and using the method in the other article.
The gpg key fingerprint from the OBS repo will be 1B07204CD71B690D409F57D24ABE1AC7557BEFF9