Exempt MathJax images from image shrinking

https://forums.ankiweb.net/t/anki-2-1-55-beta-mathjax-preview/23529/18

ts/editable/Mathjax.svelte

@@ -84,6 +84,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     src="data:image/svg+xml,{encoded}"
     class:block
     class:empty
+    class="mathjax"
     style:--vertical-center="{verticalCenter}px"
     style:--font-size="{fontSize}px"
     alt="Mathjax"

ts/editable/ResizableImage.svelte

@@ -3,7 +3,7 @@ Copyright: Ankitects Pty Ltd and contributors
 License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 -->
 <style lang="scss">
-    :global(img) {
+    :global(img:not(.mathjax)) {
         max-width: var(--editor-default-max-width);
         max-height: var(--editor-default-max-height);