Auto merge of #18059 - sendilkumarn:mito, r=nox

Using OnceCell<T> from Mitochondria

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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #13402  (github issue number if applicable).

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components/script/lib.rs

@@ -70,6 +70,7 @@ extern crate metrics;
 #[macro_use]
 extern crate mime;
 extern crate mime_guess;
+extern crate mitochondria;
 extern crate msg;
 extern crate net_traits;
 extern crate num_traits;