fix: remove bundlesize dependency

[jamesdh]

It doesn't appear the bundlesize dependency was being used for anything. I'm guessing its functionality was superseded by bundlewatch. In any case, its dependency on brotli-size, and in turn its dependency on iltorb appears to be what was causing the build failure since iltorb provides native bindings, and node-gyp was blowing up trying to build them.

Unless there is a reason to keep bundlesize, I figured it'd be far easier to just remove it instead of going down the rabbit hole that is node-gyp.

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