Auto merge of #16157 - n0max:perspective_parse_non_negative, r=emilio

Parse perspective property as non negative and add tests

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #15449  (github issue number if applicable).

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- [X] There are tests for these changes

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -11123,6 +11123,12 @@
      {}
     ]
    ],
+   "css/perspective.html": [
+    [
+     "/_mozilla/css/perspective.html",
+     {}
+    ]
+   ],
    "css/stylesheet_media_queries.html": [
     [
      "/_mozilla/css/stylesheet_media_queries.html",
@@ -22782,6 +22788,10 @@
    "001acfd664f89e45ab321bf549803ca24d44e098",
    "support"
   ],
+  "css/perspective.html": [
+   "6d455ef4b9c815d89917f496999268d7410cfa62",
+   "testharness"
+  ],
   "css/perspective_zero.html": [
    "bcb877f51808e896d8024877f945ce289dbc6b36",
    "reftest"