fix: consider oidc session events for authN milestones (#8089)

# Which Problems Are Solved

After migrating the access token events in #7822, milestones based on
authentication, resp. theses events would not be reached.

# How the Problems Are Solved

Additionally use the `oidc_session.Added` event to check for
`milestone.AuthenticationSucceededOnInstance` and
`milestone.AuthenticationSucceededOnApplication`.

# Additional Changes

None.

# Additional Context

- relates to #7822
- noticed internally

(cherry picked from commit b6c10c4c83)

internal/api/grpc/system/quotas_enabled/quota_integration_test.go

@@ -66,7 +66,7 @@ func TestServer_QuotaNotification_Limit(t *testing.T) {
 }
 
 func TestServer_QuotaNotification_NoLimit(t *testing.T) {
-	_, instanceID, IAMOwnerCTX := Tester.UseIsolatedInstance(t, CTX, SystemCTX)
+	_, instanceID, _, IAMOwnerCTX := Tester.UseIsolatedInstance(t, CTX, SystemCTX)
 	amount := 10
 	percent := 50
 	percentAmount := amount * percent / 100
@@ -148,7 +148,7 @@ func awaitNotification(t *testing.T, bodies chan []byte, unit quota.Unit, percen
 }
 
 func TestServer_AddAndRemoveQuota(t *testing.T) {
-	_, instanceID, _ := Tester.UseIsolatedInstance(t, CTX, SystemCTX)
+	_, instanceID, _, _ := Tester.UseIsolatedInstance(t, CTX, SystemCTX)
 
 	got, err := Tester.Client.System.SetQuota(SystemCTX, &system.SetQuotaRequest{
 		InstanceId:    instanceID,