Update variance-problem.mdx

[BalajiAI]

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Hi, I've a blog titled High Variance in Policy gradients which also explains about the variance problem in policy gradient and techniques for variance reduction such as baseline and actor-critics method.

I think, it would be valuable to this course readers. So I'm adding it to the reading-list.

Thanks!

[BalajiAI]

@simoninithomas would like to hear your thoughts!

[simoninithomas]

Hi 👋 ,

Very nice blogpost, it will be useful for students. I merge the PR