Doc: Remove direct links to videos from Qt Academy courses

Replace them with a link to the latest version of the
"Getting Started with Qt Creator" course.

Task-number: QTCREATORBUG-31510
Change-Id: If3ecdba3c1b593e0ccc72ea3d2bc1468013e7041
Reviewed-by: Kai Köhne <kai.koehne@qt.io>

doc/qtcreator/images/extraimages/qtcreator-extraimages.qdocconf

@@ -1,7 +1,4 @@
 {HTML.extraimages,qhp.QtCreator.extraFiles} += \
     images/commercial.png \
-    images/5OiIqFTjUZI.jpg \
     images/EhJ1eV_6RH8.jpg \
-    images/FTSvDmcAgPI.jpg \
-    images/hOx3dod5-1A.jpg \
-    images/LnVjI0I7cKs.jpg
+    images/5OiIqFTjUZI.jpg

doc/qtcreator/src/external-resources/external-resources.qdoc

@@ -9,6 +9,10 @@
     \externalpage https://www.lua.org/
     \title Lua
 */
+/*!
+    \externalpage https://www.qt.io/academy/course-catalog#getting-started-with-qt-creator
+    \title Qt Academy: Getting Started with \QC
+*/
 /*!
     \externalpage https://www.freedesktop.org/software/systemd/man/latest/systemd-coredump.html
     \title systemd-coredump

doc/qtcreator/src/overview/creator-only/creator-getting-started.qdoc

@@ -8,9 +8,8 @@
 
     \title Getting Started
 
-    To learn the basics of \QC, take the
-    \l{https://www.qt.io/academy/course-catalog#getting-started-with-qt-creator-14}
-    {Getting Started with Qt Creator} course in Qt Academy.
+    To learn the basics of \QC, take the \l{Qt Academy: Getting Started with \QC}
+    course.
 
     \table borderless
         \row

doc/qtcreator/src/projects/creator-only/creator-projects-creating.qdoc

@@ -150,9 +150,8 @@
 
     \endtable
 
-    The following video shows how to create a Qt Widgets application project:
-
-    \youtube FTSvDmcAgPI
+    To learn how to create a Qt Widgets application project, take the
+    \l{Qt Academy: Getting Started with \QC} course.
 
     For examples of creating different types of projects, see
     \l{Tutorials}.

doc/qtcreator/src/user-interface/creator-ui.qdoc

@@ -66,10 +66,8 @@
     To see where the above controls are in the UI, select
     \uicontrol Help > \uicontrol {UI Tour}.
 
-    The following video shows the parts of the UI and the \uicontrol Welcome
-    mode:
-
-    \youtube hOx3dod5-1A
+    To learn more about the parts of the UI and the \uicontrol Welcome mode, take
+    the \l{Qt Academy: Getting Started with \QC} course.
 
     \section1 What's New?
 

doc/qtcreator/src/widgets/qtdesigner-overview.qdoc

@@ -34,10 +34,8 @@
     Generally, the integrated \QD has the same functions as the standalone
     \QD. The following sections describe the differences.
 
-    The following video shows how to use the integrated \QD to create a small Qt
-    Widgets-based application:
-
-    \youtube LnVjI0I7cKs
+    To learn how to use the integrated \QD to create a small Qt Widgets-based
+    application, take the \l{Qt Academy: Getting Started with \QC} course.
 
     \section1 Code Editor Integration