Add James's illustration

Author: holly-cummins

docs/src/main/asciidoc/extension-maturity-matrix.adoc

@@ -16,7 +16,7 @@ The document header ends at the first blank line. Do not remove the blank line b
 
 What makes a good Quarkus extension? What capabilities is a Quarkus extension expected to provide? Of course, it depends on the extension you are building. But, we found a set of attributes common to many extensions. This document explains what they are.
 
-image::extension-maturity-matrix.png[A maturity matrix]
+image::extension-maturity-matrix.svg[A maturity matrix]
 
 This isn't defining an exact order, even within a single row. Different extensions have different goals, and different developers will have different views on what capabilities are most important. You may wish to (for example) prioritise a fantastic programming model over enhancing your extension's Dev UI tile. That's fine!