docs: remove unused images from docs/tutorials

[barrymcgee]

Done 🙌🏻

While I was doing some digging for #9655, I noticed the tutorial folders contained redundant image files that were no longer being used anywhere in the codebase. I have removed them.

Why? 🧐

• This is a huge codebase, cloning it to my machine took ten minutes. Removing any redundant files will help, albeit only a little. But every little helps, right? 👍🏻

• It easier to maintain a site which only contains files that are being used as there is less cognitive overload.

How to QA this change 🤓

• Grep the codebase for each file I have deleted
• You should return 0 results for each file.

[pieh]

Thanks!

They still will be in git history if someone doesn't do shallow clone (with --depth arg when cloning, but we do encourage using that in our how to contribute docs)

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