Fix typo in 'align-self' documentation: change 'an intrinsic sizes' t…

…o 'an intrinsic size' (#37638)

fixed an issue

files/en-us/web/css/align-self/index.md

@@ -60,7 +60,7 @@ align-self: unset;
     - In absolutely-positioned layouts, the keyword behaves like `start` on _replaced_ absolutely-positioned boxes, and as `stretch` on _all other_ absolutely-positioned boxes.
     - In static position of absolutely-positioned layouts, the keyword behaves as `stretch`.
     - For flex items, the keyword behaves as `stretch`.
-    - For grid items, this keyword leads to a behavior similar to the one of `stretch`, except for boxes with an {{glossary("aspect ratio")}} or an intrinsic sizes where it behaves like `start`.
+    - For grid items, this keyword leads to a behavior similar to the one of `stretch`, except for boxes with an {{glossary("aspect ratio")}} or an intrinsic size where it behaves like `start`.
     - The property doesn't apply to block-level boxes, and to table cells.
 
 - `self-start`