docs(readme): tweak width and centering for some images

[codewithdev]

Summary

I have Aligned the images and videos in the readme file for the better preview.

Related Issues/PRs

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[patrickhulce]

thanks @codewithdev for opening a PR!

I'm not sure this is really better in most cases though.

Example: HTML Report is labelled by text that is immediately above it, but centering it on large screen sizes moves it quite far from its label

👍 (original)

👎 (this PR)

[codewithdev]

Meaningful! I will add changes

[connorjclark]

Thanks @codewithdev! Can you sign the CLA?

[codewithdev]

@connorjclark I've just done it. 🕺🏻

.

[connorjclark]

Sorry for delay. At the moment we cannot merge, but if you re-merge master back into your branch/fork we can.