Update editorLink icon

[miukimiu]

Summary

The editorLink icon looks thinner when compared with other editor icons. This PR updates it to make it look thicker.

Checklist

• Check against all themes for compatibility in both light and dark modes
• [ ] Checked in mobile
• [ ] Checked in IE11 and Firefox
• [ ] Props have proper autodocs
• [ ] Added documentation examples
• [ ] Added or updated jest tests
• [ ] Checked for breaking changes and labeled appropriately
• [ ] Checked for accessibility including keyboard-only and screenreader modes
• A changelog entry exists and is marked appropriately

[cchaos]

Thanks so much for fixing this one! Can you also add a screenshot with the pixel grid?

[miukimiu]

@Caroline here's the screenshot with the pixel grid:

The editor icons are inside the 16px square but they have a 10px height. So I created my own grid margins.

[cchaos]

Just being super nit picky here, but I'd assume that these areas should be inside the pixel lines?

[miukimiu]

Now the areas are inside the pixel lines:

[cchaos]

Thanks for making that change! 👍 LGTM!