Applying lossless compression to unoptimized png files in images

[Protectator]

Why:

This PR aims to solve #298.

What's being changed:

I optimized the size of PNGs in the assets/images by using lossless compression algorithm on them. The new size of the optimized PNGs in this PR vary between 49% and 93% of their original size. This PR reduces the total size of the images by ~2457 KB.

Check off the following:

• All of the tests are passing.
• I have reviewed my changes in staging.
• For content changes, I have reviewed the localization checklist
• For content changes, I have reviewed the Content style guide for GitHub Docs.

[welcome]

Thanks for opening this pull request! A GitHub docs team member should be by to give feedback soon. In the meantime, please check out the contributing guidelines.

[heiskr]

🙏🏼 Thanks!

[janiceilene]

If you haven't already, you can add yourself to the list of contributors by creating a new comment in this PR using these instructions. Thanks again! ✨

[Protectator]

Thanks, I'll do that. I don't really know what kind of contribution that is, though ? Is that content ? Tell me if you see somethiing more appropriate.

@all-contributors please add @Protectator for content

[allcontributors]

@Protectator

This project's configuration file has malformed JSON: .all-contributorsrc. Error:: Unexpected token ] in JSON at position 8560

[Protectator]

Indeed, this ain't normal : https://github.com/github/docs/blob/main/.all-contributorsrc#L331

[Protectator]

I made a PR to repair the file first, I'll add myself after that : #391

[Protectator]

@all-contributors please add @Protectator for content

[allcontributors]

@Protectator

I've put up a pull request to add @Protectator! 🎉