chore(docs): update shortcodes docs

exampleSite/content/posts/theme-documentation-built-in-shortcodes.en.md

@@ -28,7 +28,7 @@ A shortcode is a simple snippet that can generate reasonable HTML code and confo
 
 Hugo ships with a set of predefined shortcodes that represent very common usage. These shortcodes are provided for author convenience and to keep your markdown content clean.
 
-## figure {#figure}
+## 1 figure {#figure}
 
 [Documentation of `figure`](https://gohugo.io/content-management/shortcodes#figure)
 
@@ -53,7 +53,7 @@ The HTML looks like this:
 </figure>
 ```
 
-## gist
+## 2 gist
 
 [Documentation of `gist`](https://gohugo.io/content-management/shortcodes#gist)
 
@@ -73,7 +73,7 @@ The HTML looks like this:
 <script type="application/javascript" src="https://gist.github.com/spf13/7896402.js"></script>
 ```
 
-## highlight
+## 3 highlight
 
 [Documentation of `highlight`](https://gohugo.io/content-management/shortcodes#instagram)
 
@@ -105,7 +105,7 @@ The rendered output looks like this:
 </section>
 {{< /highlight >}}
 
-## instagram
+## 4 instagram
 
 [Documentation of `instagram`](https://gohugo.io/content-management/shortcodes#instagram)
 
@@ -119,7 +119,7 @@ The rendered output looks like this:
 
 {{< instagram BWNjjyYFxVx hidecaption >}}
 
-## param
+## 5 param
 
 [Documentation of `param`](https://gohugo.io/content-management/shortcodes#param)
 
@@ -133,11 +133,11 @@ The rendered output looks like this:
 
 {{< param description >}}
 
-## ref and relref {#ref-and-relref}
+## 6 ref and relref {#ref-and-relref}
 
 [Documentation of `ref` and `relref`](https://gohugo.io/content-management/shortcodes#ref-and-relref)
 
-## tweet
+## 7 tweet
 
 [Documentation of `tweet`](https://gohugo.io/content-management/shortcodes#tweet)
 
@@ -151,7 +151,7 @@ The rendered output looks like this:
 
 {{< tweet 877500564405444608 >}}
 
-## vimeo
+## 8 vimeo
 
 [Documentation of `vimeo`](https://gohugo.io/content-management/shortcodes#vimeo)
 
@@ -165,7 +165,7 @@ The rendered output looks like this:
 
 {{< vimeo 146022717 >}}
 
-## youtube
+## 9 youtube
 
 [Documentation of `youtube`](https://gohugo.io/content-management/shortcodes#youtube)