feat: add 404 not found page

[afzal442]

Signed-off-by: afzal442 afzal442@gmail.com

Description

Fix #170

Additional context

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What is the purpose of this pull request?

• Bug fix
• New feature
• Other

[netlify]

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[trsvchn]

Thanks @afzal442!
Let me run the deploy preview!

[trsvchn]

@afzal442 Looks like we have some linting issues here

https://github.com/pytorch-ignite/code-generator/pull/178/checks?check_run_id=3781076007#step:9:13

Please take a look at our CONTRIBUTING how to run formatters.

[trsvchn]

Thanks @afzal442 ! It works!
https://deploy-preview-178--code-generator.netlify.app/foo

But let's try to add top bar and a footer, to get smth like this:

Inspired by pytorch 404 page

[afzal442]

@trsvchn I am done. 🪧 Plz also add hacktoberfest label as well. 😵‍💫

[trsvchn]

Thanks @afzal442 ! This looks much better :)

Let's split the page content into several lines, to fit into the following template:

Error Code

Error Short Description

Error Long Description

How to solve

---

navbar

---

404

Page Not Found

Oops we couldn't find that page.

Try going home

---

footer

---

[trsvchn]

Thanks for the updates @afzal442 !

I left some nit comments related to wording.