docs: update readme to reflect issuer change
@@ -201,7 +201,7 @@ You can use ORY Hydra without a database, but be aware that restarting, scaling
or stopping the container will **lose all data**:
```
-$ docker run -e "DATABASE_URL=memory" -d --name my-hydra -p 4444:4444 oryd/hydra
+$ docker run -e "DATABASE_URL=memory" -e "ISSUER=https://localhost:4444/" -d --name my-hydra -p 4444:4444 oryd/hydra
ec91228cb105db315553499c81918258f52cee9636ea2a4821bdb8226872f54b
```
