Fix the flag of the Russian Soviet Federative Socialist Republic

The flag of the Russian Soviet Federative Socialist Republic (1917-22) is inconsistent. In the issuers list, it's just a question mark. But besides the coins, it is the Russian flag, which is probably coming from the parent issuer of Russia.

The RSFSR had its own flag, didn't use the white-blue-red Russian flag:

https://en.wikipedia.org/wiki/File:Flag_of_the_Russian_Soviet_Federative_Socialist_Republic_(1918%E2%80%931925).svg

Heavy agree on this. I've had a request asking for exactly this over on the Referee forum since October, 2025 haha

https://en.numista.com/forum/topic167769.html#p1286408

Closed, as the request would be now duplicated.

Just a small update. The new flag does propagate to the coins properly, but the flag in the dropdown menu of the issuers is just an empty placeholder.