[wasm] Enable closure compiler for dotnet.js

[CoffeeFlux]

See #51446, initial estimate of 15K compressed savings.

cc: @benaadams

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Issue Details

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See #51446, initial estimate of 15K compressed savings.

cc: @benaadams

Author:	CoffeeFlux
Assignees:	-
Labels:	arch-wasm, area-Build-mono, size-reduction
Milestone:	6.0.0