Fix some clazy warning

autotests/testtodotooltip.cpp

@@ -44,7 +44,7 @@ using namespace KCalUtils::IncidenceFormatter;
 // Create a to-do that may or may not be an all-day to-do, may or may nor recur,
 // and with the given start and due dates (which may be invalid).
 // Other to-do fields are fixed.
-static KCalendarCore::Todo::Ptr makeToDo(bool allday, bool recurs, QDateTime dtStart, QDateTime dtDue)
+static KCalendarCore::Todo::Ptr makeToDo(bool allday, bool recurs, const QDateTime &dtStart, const QDateTime &dtDue)
 {
     KCalendarCore::Todo::Ptr todo{new KCalendarCore::Todo};
     todo->setSummary(SUMMARY);

src/incidenceformatter.cpp

@@ -3308,12 +3308,12 @@ QString IncidenceFormatter::recurrenceString(const Incidence::Ptr &incidence)
     return recurStr;
 }
 
-QString IncidenceFormatter::timeToString(const QTime &time, bool shortfmt)
+QString IncidenceFormatter::timeToString(QTime time, bool shortfmt)
 {
     return QLocale().toString(time, shortfmt ? QLocale::ShortFormat : QLocale::LongFormat);
 }
 
-QString IncidenceFormatter::dateToString(const QDate &date, bool shortfmt)
+QString IncidenceFormatter::dateToString(QDate date, bool shortfmt)
 {
     return QLocale().toString(date, (shortfmt ? QLocale::ShortFormat : QLocale::LongFormat));
 }

src/incidenceformatter.h

@@ -158,7 +158,7 @@ KCALUTILS_EXPORT QStringList reminderStringList(const KCalendarCore::Incidence::
   @param shortfmt If true, display info in short format.
   @see dateToString(), dateTimeToString().
 */
-KCALUTILS_EXPORT QString timeToString(const QTime &time, bool shortfmt = true);
+KCALUTILS_EXPORT QString timeToString(QTime time, bool shortfmt = true);
 
 /**
   Build a QString date representation of a QDate object.
@@ -167,7 +167,7 @@ KCALUTILS_EXPORT QString timeToString(const QTime &time, bool shortfmt = true);
   @param shortfmt If true, display info in short format.
   @see dateToString(), dateTimeToString().
 */
-KCALUTILS_EXPORT QString dateToString(const QDate &date, bool shortfmt = true);
+KCALUTILS_EXPORT QString dateToString(QDate date, bool shortfmt = true);
 
 KCALUTILS_EXPORT QString formatStartEnd(const QDateTime &start, const QDateTime &end, bool isAllDay);