fix: markdown paragraph margin (#8289)

web/app/components/base/markdown.tsx

     return (
       <>
         <ImageGallery srcs={[children_node[0].properties.src]} />
-        <div>{paragraph.children.slice(1)}</div>
+        <p>{paragraph.children.slice(1)}</p>
       </>
     )
   }
-  return <div>{paragraph.children}</div>
+  return <p>{paragraph.children}</p>
 }
 
 const Img = ({ src }: any) => {

web/app/styles/markdown.scss

 .markdown-body h4,
 .markdown-body h5,
 .markdown-body h6 {
-  margin-top: 24px;
-  margin-bottom: 16px;
+  padding-top: 12px;
+  margin-bottom: 12px;
   font-weight: var(--base-text-weight-semibold, 600);
   line-height: 1.25;
 }
 
-
-.markdown-body p {
-  margin-top: 0;
-  margin-bottom: 10px;
-}
-
 .markdown-body blockquote {
   margin: 0;
   padding: 0 8px;
 .markdown-body pre,
 .markdown-body details {
   margin-top: 0;
-  margin-bottom: 16px;
+  margin-bottom: 12px;
 }
 
 .markdown-body blockquote> :first-child {