Move findfiles example into manual tests

The example follows bad and outdated practices:

- running time consuming and I/O heavy workload in the GUI thread
- calling processEvents to keep the UI responsive
- showing results only at the end of a search rather than continuously

Perhaps this example can be rewritten at some point to apply modern
practices (at least use a thread and emit signals), but it seems
to have low overall educational value.

Moving it to be a manual test for now.

Fixes: QTBUG-111002
Pick-to: 6.5
Change-Id: Id630fd4599096448ea4f96bcbf977b11a039796f
Reviewed-by: Axel Spoerl <axel.spoerl@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

examples/widgets/dialogs/CMakeLists.txt

@@ -6,7 +6,6 @@ if(QT_FEATURE_wizard)
     qt_internal_add_example(trivialwizard)
 endif()
 qt_internal_add_example(extension)
-qt_internal_add_example(findfiles)
 qt_internal_add_example(standarddialogs)
 qt_internal_add_example(tabdialog)
 if(QT_FEATURE_wizard AND TARGET Qt6::PrintSupport)

examples/widgets/dialogs/dialogs.pro

@@ -3,7 +3,6 @@ QT_FOR_CONFIG += widgets
 TEMPLATE      = subdirs
 SUBDIRS       = classwizard \
                 extension \
-                findfiles \
                 licensewizard \
                 standarddialogs \
                 tabdialog \

src/widgets/dialogs/qprogressdialog.cpp

@@ -215,7 +215,7 @@ void QProgressDialogPrivate::_q_disconnectOnClose()
 
   \image fusion-progressdialog.png A progress dialog shown in the Fusion widget style.
 
-  \sa QDialog, QProgressBar, {Find Files Example}, {Pixelator Example}
+  \sa QDialog, QProgressBar, {Pixelator Example}
 */