docs: add missing quote (#22771)

mottox2 · gatsbybot · web-flow · commit 2bb39c191631 · 2020-04-03T16:39:49.000-04:00
Co-authored-by: gatsbybot &lt;mathews.kyle+gatsbybot@gmail.com&gt;
diff --git a/docs/docs/recipes/working-with-plugins.md b/docs/docs/recipes/working-with-plugins.md
@@ -97,7 +97,7 @@ my-plugin
 ```javascript:title=gatsby-site/gatsby-config.js
 module.exports = {
   plugins: [
-    require.resolve(`../my-plugin), // highlight-line
+    require.resolve(`../my-plugin`), // highlight-line
   ],
 }
 ```

Original file line number	Diff line number	Diff line change
`@@ -97,7 +97,7 @@ my-plugin`
`97`	`97`	```javascript:title=gatsby-site/gatsby-config.js
`98`	`98`	`module.exports = {`
`99`	`99`	`plugins: [`
`100`		- require.resolve(`../my-plugin), // highlight-line
	`100`	+ require.resolve(`../my-plugin`), // highlight-line
`101`	`101`	`],`
`102`	`102`	`}`
`103`	`103`	```