fix: handle side-effect only modules in normalizeRuntimeShare

[simonihmig]

This is fixing an issue if your shared deps cover a module without exports (only side-effects). Ran into this when sharing lit/ which covers lit/polyfill-support. The browser seems to expose this with an (empty) special module namespace object as default. The __mfNormalizeRuntimeShare function would then return this one instead of the original module object. In the const exportModule = normalizedModule === mod ? {...mod} : normalizedModule; statement, normalizedModule would not be equal to mod, so it would try to defineProperty on that namespace object, which fails as that is a exotic esm object that you cannot mutate.

This can be reproduced when adding lit/ in the lit example app here.

[pkg-pr-new]

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npm i https://pkg.pr.new/@module-federation/vite@718

commit: 61743fc

[gioboa]

Tests With Different Frameworks

[gioboa]

Thanks for your amazing help @simonihmig