Improve comment on IDSeparator

internal/testutils/broker.go

@@ -17,7 +17,7 @@ const (
 	objectPathFmt = "/com/ubuntu/authd/%s"
 	interfaceFmt  = "com.ubuntu.authd.%s"
 
-	// IDSeparator is the value used to trim the sessionID in the broker mock.
+	// IDSeparator is the value used to append values to the sessionID in the broker mock.
 	IDSeparator = "_separator_"
 )
 
@@ -281,8 +281,10 @@ func (b *BrokerBusMock) CancelIsAuthorized(sessionID string) (dbusErr *dbus.Erro
 }
 
 // parseSessionID is wrapper around the sessionID to remove some values appended during the tests.
+//
+// The sessionID can have multiple values appended to differentiate between subtests and avoid concurrency conflicts,
+// and only the last value (i.e. "..._separator_ID-session_id") will be considered.
 func parseSessionID(sessionID string) string {
-	// We need to prefix the sessionID with the test name in some tests, so we have to consider this here in the broker.
 	cut := strings.Split(sessionID, IDSeparator)
 	if len(cut) == 0 {
 		return ""