Function handle_set_tenant_metadata 

pub async fn handle_set_tenant_metadata(
    __arg0: State<Arc<Context>>,
    __arg1: Path<Uuid>,
    __arg2: Json<SetTenantMetadataRequest>,
) -> Result<Json<TenantResponse>, StatusCode>

Handle POST /tenants/resources/tenants/v1/{id}/metadata

Merges the given keys into the tenant’s metadata. Keys that are not mentioned are left in place, as in Frontegg.