Add an extra line break at the end of a ref definition

app/assets/javascripts/vue_shared/components/rich_content_editor/services/build_html_to_markdown_renderer.js

@@ -96,7 +96,7 @@ const buildHTMLToMarkdownRender = (baseRenderer, formattingPreferences = {}) =>
       const isReferenceDefinition = Boolean(node.dataset.sseReferenceDefinition);
 
       return isReferenceDefinition
-        ? `\n\n${node.innerText}\n`
+        ? `\n\n${node.innerText}\n\n`
         : baseRenderer.convert(node, subContent);
     },
   };

spec/frontend/vue_shared/components/rich_content_editor/services/build_html_to_markdown_renderer_spec.js

@@ -178,7 +178,9 @@ describe('rich_content_editor/services/html_to_markdown_renderer', () => {
     });
 
     it('returns raw text when pre node has sse-reference-definitions class', () => {
-      expect(htmlToMarkdownRenderer['PRE CODE'](node, subContent)).toBe(`\n\n${node.innerText}\n`);
+      expect(htmlToMarkdownRenderer['PRE CODE'](node, subContent)).toBe(
+        `\n\n${node.innerText}\n\n`,
+      );
     });
 
     it('returns base result when pre node does not have sse-reference-definitions class', () => {