Only bundle the release build, and don't import src in tests (#13978)

* Only bundle the release build, and don't import `src` in tests

* Use file extension to signal skipping

* Remove unnecessary config change

* Fix imports

packages/babel-parser/test/unit/tokenizer/types.skip-bundled.js

@@ -1,4 +1,4 @@
-import { tt, tokenOperatorPrecedence } from "../../../src/tokenizer/types.js";
+import { tt, tokenOperatorPrecedence } from "../../../lib/tokenizer/types.js";
 
 describe("token types", () => {
   it("should check if the binOp for relational === in", () => {