Make preview panel expiration date use local time (#2382)

Adds call to toLocalTime() to convert expiration date string
to correct timezone instead of UTC, which matches the date string
in the database view.

src/gui/EntryPreviewWidget.cpp

@@ -179,7 +179,7 @@ void EntryPreviewWidget::updateEntryGeneralTab()
 
     const TimeInfo entryTime = m_currentEntry->timeInfo();
     const QString expires =
-        entryTime.expires() ? entryTime.expiryTime().toString(Qt::DefaultLocaleShortDate) : tr("Never");
+        entryTime.expires() ? entryTime.expiryTime().toLocalTime().toString(Qt::DefaultLocaleShortDate) : tr("Never");
     m_ui->entryExpirationLabel->setText(expires);
 }