[RFC]: Refactor random number generation in JS benchmarks for `stats/base/dists` (tracking issue)

This RFC proposes improving random number generation in JS benchmarks for remaining packages in [`stats/base/dists`](https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/base/dists).

Start by reviewing the packages under lib/node_modules/@stdlib/stats/base/dists and the existing JavaScript benchmarks. Identify which remaining packages need random-number-generation changes, then confirm that the benchmark updates consistently cover those packages and improve the proposed behavior.

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