chore: update link to grafana model (#41)

Updated link to Grafana model

README.md

@@ -69,7 +69,7 @@ The OpenFGA [Getting Started](https://openfga.dev/docs/modeling/getting-started)
 - [virtool/virtool](https://github.com/virtool/virtool/blob/c621ba6a22bfe3464fe59287337029e42295cfcb/virtool/authorization/openfga.py#L123)
 - [concrete-utopia/utopia](https://github.com/concrete-utopia/utopia/blob/master/utopia-remix/fga/model.fga)
 - [Cross-Lab-Project/crosslab](https://github.com/Cross-Lab-Project/crosslab/blob/main/services/authorization/relation_model.fga)
-- [grafana/grafana](https://github.com/grafana/grafana/blob/main/pkg/services/authz/zanzana/schema/schema.fga)
+- [grafana/grafana](https://github.com/grafana/grafana/tree/main/pkg/services/authz/zanzana/schema)
 - [sourcegraph/sourcegraph-public-snapshot](https://github.com/sourcegraph/sourcegraph-public-snapshot/blob/main/cmd/enterprise-portal/service/iam_model.fga)
 - [klothoplatform/infracopilot](https://github.com/klothoplatform/infracopilot/blob/main/src/auth_service/model.fga)
 - [ZEISS/knox](https://github.com/ZEISS/knox/blob/main/schema/auth.fga)