Reverted the contentIndex and RSS component code changes because of the build issue

Author: joshwingreene

quartz/components/RSS.tsx

@@ -4,7 +4,7 @@ import { classNames } from "../util/lang"
 function RSS({ displayClass }: QuartzComponentProps) {
   return (
     <div class={classNames(displayClass, "rss")}>
-        <a href="/garden.rss">
+        <a href="/index.xml">
             <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512">
                 <path d="M0 64C0 46.3 14.3 32 32 32c229.8 0 416 186.2 416 416c0 17.7-14.3 32-32 32s-32-14.3-32-32C384 253.6 226.4 96 32 96C14.3 96 0 81.7 0 64zM0 416a64 64 0 1 1 128 0A64 64 0 1 1 0 416zM32 160c159.1 0 288 128.9 288 288c0 17.7-14.3 32-32 32s-32-14.3-32-32c0-123.7-100.3-224-224-224c-17.7 0-32-14.3-32-32s14.3-32 32-32z"/>
             </svg>