Auto merge of #19849 - gterzian:update_wpt, r=jdm

WPT tests: Remove custom cache script, use trickle option instead

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Follow up on https://github.com/servo/servo/pull/19350 @jdm

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

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -12495,11 +12495,6 @@
      {}
     ]
    ],
-   "mozilla/resources/http-cache-trickle.py": [
-    [
-     {}
-    ]
-   ],
    "mozilla/resources/http-cache.js": [
     [
      {}
@@ -66395,11 +66390,11 @@
    "testharness"
   ],
   "mozilla/http-cache-xhr.html": [
-   "d4747fdc9ec6acc50718c13a668451987a44d219",
+   "56c44d5100ec2b5a585192e4ec319bb133123c93",
    "testharness"
   ],
   "mozilla/http-cache.html": [
-   "33827dc9bdb0efcbcae4f730086693be315cfc14",
+   "929fdc40e9a193d0ead4c95e2d21d030d27d4bf0",
    "testharness"
   ],
   "mozilla/iframe-unblock-onload.html": [
@@ -72074,12 +72069,8 @@
    "78686147f85e4146e7fc58c1f67a613f65b099a2",
    "support"
   ],
-  "mozilla/resources/http-cache-trickle.py": [
-   "48f4e32ec2e1c1b6d47e89254045b398c1d84d40",
-   "support"
-  ],
   "mozilla/resources/http-cache.js": [
-   "4bf71e1f328e778990eb756741a3be58f4f57ef6",
+   "c6b1ee9def26d4e12a1b93e551c225f82b4717c2",
    "support"
   ],
   "mozilla/resources/iframe_contentDocument_inner.html": [