Move digital clock example to manual test

Change-Id: I043c0060a71d9de2f3e74aab0759d07a20880c3a
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
(cherry picked from commit 65e7303ec906fb64930772a06fed647f41b54391)
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

examples/widgets/doc/src/digitalclock.qdoc

@@ -1,51 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
-
-/*!
-    \example widgets/digitalclock
-    \title Digital Clock Example
-    \ingroup examples-widgets
-    \brief The Digital Clock example shows how to use QLCDNumber to display a
-    number with LCD-like digits.
-
-    \borderedimage digitalclock-example.png
-    \caption Screenshot of the Digital Clock example
-
-    This example also demonstrates how QTimer can be used to update a widget
-    at regular intervals.
-
-    \section1 DigitalClock Class Definition
-
-    The \c DigitalClock class provides a clock widget showing the time with
-    hours and minutes separated by a blinking colon. We subclass QLCDNumber
-    and implement a private slot called \c showTime() to update the clock
-    display:
-
-    \snippet widgets/digitalclock/digitalclock.h 0
-
-    \section1 DigitalClock Class Implementation
-
-    \snippet widgets/digitalclock/digitalclock.cpp 0
-
-    In the constructor, we first change the look of the LCD numbers. The
-    QLCDNumber::Filled style produces raised segments filled with the
-    foreground color (typically black). We also set up a one-second timer
-    to keep track of the current time, and we connect
-    its \l{QTimer::timeout()}{timeout()} signal to the private \c showTime() slot
-    so that the display is updated every second. Then, we
-    call the \c showTime() slot; without this call, there would be a one-second
-    delay at startup before the time is shown.
-
-    \snippet widgets/digitalclock/digitalclock.cpp 1
-    \snippet widgets/digitalclock/digitalclock.cpp 2
-
-    The \c showTime() slot is called whenever the clock display needs
-    to be updated.
-
-    The current time is converted into a string with the format "hh:mm".
-    When QTime::second() is a even number, the colon in the string is
-    replaced with a space. This makes the colon appear and vanish every
-    other second.
-
-    Finally, we call QLCDNumber::display() to update the widget.
-*/

examples/widgets/widgets/CMakeLists.txt

@@ -4,7 +4,6 @@
 qt_internal_add_example(analogclock)
 qt_internal_add_example(calculator)
 qt_internal_add_example(calendarwidget)
-qt_internal_add_example(digitalclock)
 qt_internal_add_example(groupbox)
 qt_internal_add_example(imageviewer)
 qt_internal_add_example(lineedits)

examples/widgets/widgets/widgets.pro

@@ -2,7 +2,6 @@ TEMPLATE      = subdirs
 SUBDIRS       = analogclock \
                 calculator \
                 calendarwidget \
-                digitalclock \
                 groupbox \
                 imageviewer \
                 lineedits \