Improvement/provide with and height for gravatar avatar

[obfischer]

Prerequisites

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• This pull request fixes a bug.
• This pull request adds a feature.
• This pull request introduces breaking change.

Description

The img tag for an avatar via Gravatar now specifies the width and height of the image.

Providing these attributes helps to avoid Cumulative Layout Shift. Avoiding this improves the page speed ranking of the page.

Issues Resolved

There is no corresponding issue.

Checklist

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General

• Describe what changes are being made
• Explain why and how the changes were necessary and implemented respectively
• Reference issue with #<ISSUE_NO> if applicable

Resources

• If you have changed any SCSS code, run make release to regenerate all CSS files

Contributors

• Add yourself to CONTRIBUTORS.md if you aren't on it already

[obfischer]

I can extend the change so that the also for a local avatar image these attributes can be specified. Please let me know if I should provide a solution for this too.