use exec instead of matchAll while keeping structure

[RaananW]

Babylon native's js engine doesn't support matchAll (an ES2020 feature).

Instead, I am recreating the same structure using .exec.

Performance-wise it is on-par and even faster (at least on my benchmarks. See here - https://jsbench.me/wblj4eghw5/1)

[bjsplat]

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[bjsplat]

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