update changelog

src/fsfw/tasks/FixedTimeslotTaskIF.h

@@ -42,6 +42,7 @@ class FixedTimeslotTaskIF : public PeriodicTaskIF {
    */
   virtual ReturnValue_t addSlot(object_id_t execId, ExecutableObjectIF* obj, uint32_t slotTimeMs,
                                 int8_t executionStep) = 0;
+
   /**
    * Check whether the sequence is valid and perform all other required
    * initialization steps which are needed after task creation