[dll] run babel on all modules that aren't explicitly excluded #59923
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Fixes #59833
While trying to find a solution that allows us to validate that our DLL bundles don't include JS that breaks IE I started digging into possibly building a custom Webpack plugin and/or loader. During this investigation I realized something... Webpack is already parsing all of the code in our node_modules in order to determine dependencies and my fears of the performance impact of running node_modules through babel might be misplaced. I then decided to test out the performance impact of transpiling all modules in the DLL with babel and I'm pretty sure we don't actually see that much of a performance impact (like 2-4 seconds in dev).
I'm pushing this change up with shame, as I've been pushing back on making this change for so long and pushed a lot of people to work around this, but hopefully people will forgive me...
Also, I'd like to make sure that performance is still manageable for other team members as I'm testing on an iMac Pro.