Embed Matrix icon as SVG (#21890)
Embed the SVG icon directly, making further invertion unnecessary
because the icon color can now follow text color.
<img width="240" alt="Screenshot 2022-11-21 at 20 16 32"
src="https://user-images.githubusercontent.com/115237/203142189-89f20de9-c0bd-4d05-92c0-44dadf20d78f.png">
<img width="245" alt="Screenshot 2022-11-21 at 20 16 46"
src="https://user-images.githubusercontent.com/115237/203142191-658239ba-1859-49c6-91ad-10ddf14780d0.png">
