chore: Update `swc_core` to `v0.76.6` (#4937)
### Description
Updates `swc_core` to `v0.76.x`, which adds support for `Explicit
Resource Management` (stage 3)
### Testing Instructions
Look at CI.
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next.js counterpart: https://github.com/vercel/next.js/pull/49792
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Closes WEB-1038
