Update 'Dynamically Loading Graphics Drivers'

Dynamically-Loading-Graphics-Drivers.md

@@ -1,4 +1,3 @@
-
 In addition to the build time configuration, Qt supports choosing and loading the OpenGL implementation at runtime. To use this mode, pass -opengl dynamic to the configure script.
 
 configure -opengl dynamic
@@ -17,3 +16,5 @@ Qt::AA_UseDesktopOpenGL Equivalent to setting QT_OPENGL to desktop.
 Qt::AA_UseOpenGLES Equivalent to setting QT_OPENGL to angle.
 Qt::AA_UseSoftwareOpenGL Equivalent to setting QT_OPENGL to software.
 ```
+
+[source](https://doc.qt.io/qt-5/windows-requirements.html)