Remove the fuzz tests (issue 19297)

Reasons for removal:

 - These tests never generated any warnings from OSS-Fuzz, in over a year.

 - An error thrown during image decoding will lead to a broken/missing image, not a security problem.

 - These tests rely on the Jazzer.js library, which has a number of problems: It now causes failures in Node.js v23 in the CI tests, it's no longer being maintained upstream, and it lacks support for some (fairly common) CPU architectures.

eslint.config.mjs

@@ -352,15 +352,6 @@ export default [
       "jasmine/prefer-toHaveBeenCalledWith": "off",
     },
   },
-  {
-    files: jsFiles("test/fuzz"),
-    rules: {
-      "import/no-unresolved": [
-        "error",
-        { ignore: [".*/build/image_decoders/.*"] },
-      ],
-    },
-  },
   {
     files: jsFiles("test/unit"),
     rules: {