fix(theme-classic): apply width/height for footer logos without href

[kgajera]

Motivation

Fixes #6503

Have you read the Contributing Guidelines on pull requests?

Yes

Test Plan

I manually tested the Footer component using my local packages to ensure the height and width attributes were set on the logo image element with the following configuration:

footer: {
  logo: {
    alt: "Logo",
    src: "img/logo.png",
    height: 50,
    width: 50,
  }
}

[Josh-Cena]

LGTM

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[github-actions]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟠 Performance	69
🟢 Accessibility	100
🟢 Best practices	100
🟢 SEO	100
🟢 PWA	92

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