Adding Works on Arm logo on our English website.

[junaruga]

This PR is to add Arm's logo sponsoring us for a Ubuntu Arm neoverse server (RubyCI - "Ubuntu arm neoverse") as their project Works on Arm to our English website: https://www.ruby-lang.org/en/about/website/ as our appreciation.

I got the logo image from "Arm Blue Logo" on this page. The url is https://www.arm.com/-/media/global/logos/Arm-logo-blue-pms313.svg . The image file is originally .svg file. I converted it to png file (image size 237 x 72 pixels).

You can check the updated document here on my forked repository.

I am going to confirm our folks at Arm before merging this PR.

[junaruga]

I would ask you for the PR's review after I can contact with people at Arm.

[sorah]

Changes look good so approving, but acknowledge to hold merging until Arm team's confirmation

[junaruga]

A person at Arm told me that they would prefer to use Works on Arm's logo rather than Arm's logo. And I am asking them to get the Works on Arm's logo image file now.

[junaruga]

A person at Arm told me that they would prefer to use Works on Arm's logo rather than Arm's logo. And I am asking them to get the Works on Arm's logo image file now.

I received a Works on Arm logo image file (png file) from a person at Arm. The file was the width x height = 7808px x 650px (file size: 751.3 KB) with a transparent background color. As the image size was bigger than other images under the images/sponsor/*.png files, I scaled the image size down by myself into the 300px x 26px (file size: 9.5 KB).

The reason why I decided the width 300px is because the image file with longest width is mackerel.png whose width is 300px. Though the mackerel.png has padding spaces unilke the works-on-arm.png, the appearance is a bit different.

You can check the updated document here on my forked repository again.

I rebased this PR updating the commit message too on the latest master branch.

[junaruga]

Could you review again? Thank you.

[hsbt]

@junaruga Thank you ❤️