doc: Change reference to logos from PNG to SVG
@@ -179,7 +179,7 @@ Advanced
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If you need to do more to customize the logo than simply replacing the existing
-PNG, then you can also override the _brand.html through a custom theme. To use
+SVG, then you can also override the _brand.html through a custom theme. To use
this technique, simply add a ``templates/header/_brand.html`` to the root of
your custom theme, and add markup directly to the file. For an example of how
to do this, see
