Remove :target-within (mdn#40930)

* Remove `:target-within`

* Format

---------

Co-authored-by: Joshua Chen <sidachen2003@gmail.com>

Author: lukewarlow

files/en-us/_redirects.txt

@@ -12108,6 +12108,7 @@
 /en-US/docs/Web/CSS/:nth-last-col	/en-US/docs/Web/CSS/:nth-last-of-type
 /en-US/docs/Web/CSS/:nth-last-of-type()	/en-US/docs/Web/CSS/:nth-last-of-type
 /en-US/docs/Web/CSS/:nth-of-type()	/en-US/docs/Web/CSS/:nth-of-type
+/en-US/docs/Web/CSS/:target-within	/en-US/docs/Web/CSS
 /en-US/docs/Web/CSS/@-moz-document	/en-US/docs/Web/CSS/@document
 /en-US/docs/Web/CSS/@font-face/font-variant	/en-US/docs/Web/CSS/@font-face
 /en-US/docs/Web/CSS/@media/aural	/en-US/docs/Web/CSS/@media

files/en-us/_wikihistory.json

@@ -74071,10 +74071,6 @@
       "j.j."
     ]
   },
-  "Web/CSS/:target-within": {
-    "modified": "2020-12-04T07:48:58.177Z",
-    "contributors": ["rachelandrew"]
-  },
   "Web/CSS/:user-invalid": {
     "modified": "2020-11-20T11:42:30.261Z",
     "contributors": [