LibWeb/SVG: Add FEGaussianBlurElement

Author: https://github.com/ananas-dev
Commit: 5d85959f5f
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5028
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/CMakeLists.txt

@@ -825,6 +825,7 @@ set(SOURCES
     SVG/SVGEllipseElement.cpp
     SVG/SVGFEBlendElement.cpp
     SVG/SVGFEFloodElement.cpp
+    SVG/SVGFEGaussianBlurElement.cpp
     SVG/SVGFilterElement.cpp
     SVG/SVGForeignObjectElement.cpp
     SVG/SVGGElement.cpp