Secretkeeper: use Ed25519 identity key

Test: VtsSecretkeeperTargetTest
Change-Id: I27aebb8913c34f043b7ccc7b6e23969377313e1e
diff --git a/security/secretkeeper/default/src/lib.rs b/security/secretkeeper/default/src/lib.rs
index 412ad45..eb7817c 100644
--- a/security/secretkeeper/default/src/lib.rs
+++ b/security/secretkeeper/default/src/lib.rs
@@ -53,8 +53,12 @@
             let mut crypto_impls = boring::crypto_trait_impls();
             let storage_impl = Box::new(store::InMemoryStore::default());
             let sk_ta = Rc::new(RefCell::new(
-                SecretkeeperTa::new(&mut crypto_impls, storage_impl)
-                    .expect("Failed to create local Secretkeeper TA"),
+                SecretkeeperTa::new(
+                    &mut crypto_impls,
+                    storage_impl,
+                    coset::iana::EllipticCurve::Ed25519,
+                )
+                .expect("Failed to create local Secretkeeper TA"),
             ));
             let mut ag_ta = AuthGraphTa::new(
                 AuthGraphParticipant::new(crypto_impls, sk_ta.clone(), MAX_OPENED_SESSIONS)