Exclude skia/third_party/icu from the license crawl (#4684)

tools/licenses/lib/main.dart

@@ -1809,6 +1809,7 @@ class RepositorySkiaThirdPartyDirectory extends RepositoryGenericThirdPartyDirec
   bool shouldRecurse(fs.IoNode entry) {
     return entry.name != 'giflib' // contains nothing that ends up in the binary executable
         && entry.name != 'freetype' // we use our own version
+        && entry.name != 'icu' // we use our own version
         && entry.name != 'libjpeg-turbo' // we use our own version
         && entry.name != 'libpng' // we use our own version
         && entry.name != 'lua' // not linked in