Adjust image file path (#1029)

Fix Antora build
Fixes #1028

samples/extensions/dynamic_primitive_clipping/README.adoc

@@ -23,7 +23,7 @@ ifdef::site-gen-antora[]
 TIP: The source for this sample can be found in the https://github.com/KhronosGroup/Vulkan-Samples/tree/main/samples/extensions/dynamic_primitive_clipping[Khronos Vulkan samples github repository].
 endif::[]
 
-image::screenshot.png[]
+image::./screenshot.png[]
 
 == Overview