Auto merge of #20858 - tigercosmos:yy1, r=jdm

move test `dom-element-scroll.html` from mozilla to wpt

<!-- Please describe your changes on the following line: -->
The test `dom-element-scroll.html` was originally landed on #19127.
It was designed for testing `scrollLeft` and `scrollTop`.
It is not only for servo. I thought I put a wrong place at that time. It should not be under `mozilla`. It's better placed under `wpt`.

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -31791,12 +31791,6 @@
      {}
     ]
    ],
-   "css/cssom-view/dom-element-scroll.html": [
-    [
-     "/_mozilla/css/cssom-view/dom-element-scroll.html",
-     {}
-    ]
-   ],
    "css/empty-keyframes.html": [
     [
      "/_mozilla/css/empty-keyframes.html",
@@ -61182,10 +61176,6 @@
    "16a4dd68da41156fbdd139b4a56547f94ad4dbe7",
    "support"
   ],
-  "css/cssom-view/dom-element-scroll.html": [
-   "247b85d5988878a7b27bc9f0f7b817085725c038",
-   "testharness"
-  ],
   "css/data_img_a.html": [
    "323bf50369f98ed02acccdd3a5824e38d3f353bf",
    "reftest"