Fix a couple of typos/misspellings

[cwood1967]

I was just reading the vae example and noticed a couple misspellings.

[ChaiBapchya]

Unable to see the diff properly rendered on the website. Curious what have u changed in the image section? @cwood1967

[cwood1967]

Just two very minor things -
I changed the bold in this:

"A straightforward way to approach VAE is through the construction of the well-known Expectation-Maximization (EM) algorithm. Please refer to this tutorial or this blog as a refresher on EM. Just to quicly recap a few key elements in EM: insteand of optimizing the

With the bold below:

"A straightforward way to approach VAE is through the construction of the well-known Expectation-Maximization (EM) algorithm. Please refer to this tutorial or this blog as a refresher on EM. Just to quickly recap a few key elements in EM: instead of optimizing the

[ChaiBapchya]

Thanks