Wrap inline footnote definitions in a paragraph tag.

This is to match the behavior of the upstream org html exporter.

src/intermediate/paragraph.rs

@@ -29,3 +29,16 @@ intermediate!(
         })
     }
 );
+
+impl IParagraph {
+    pub(crate) async fn artificial<'orig, 'parse>(
+        _intermediate_context: crate::intermediate::IntermediateContext<'orig, 'parse>,
+        children: Vec<IObject>,
+        post_blank: organic::types::PostBlank,
+    ) -> Result<IParagraph, CustomError> {
+        Ok(IParagraph {
+            children,
+            post_blank,
+        })
+    }
+}