Backport #35556 (#35558)

* Use param to set Bootstrap version in Contents doc

Co-authored-by: XhmikosR <xhmikosr@gmail.com>

site/content/docs/4.6/getting-started/contents.md

@@ -130,9 +130,9 @@ bootstrap/
 │   ├── css/
 │   └── js/
 ├── site/
-│   └──content/
+│   └── content/
-|      └──docs/
+|       └── docs/
-|         └── 4.6/
+|           └── {{< param docs_version >}}/
 |               └── examples/
 ├── js/
 └── scss/