add label.iconSVG key

[icy-comet]

What does this PR change? What problem does it solve?
This PR adds label.iconSVG key under site params. It can be used to embed the SVG directly for easier styling, e.g. for handling the change between dark and light mode.

Was the change discussed in an issue or in the Discussions before?
Closes #974.

PR Checklist

• This change adds/updates translations and I have used the template present here.
• I have enabled maintainer edits for this PR.
• I have verified that the code works as described/as intended.
• This change adds a Social Icon which has a permissive license to use it.
• This change does not include any CDN resources/links.
• This change does not include any unrelated scripts such as bash and python scripts.
• This change updates the overridden internal templates from HUGO's repository.

[adityatelange]

I didn't mean for it to come across as a complaint.

I was just looking for a confirmation on the matter to proceed with the PR.

I had already said we can go ahead in discord. Anyways about the svg height, we don't need to implement that.
It is redundant to add iconHeight to replace height in svg. User can add height directly in svg.

Originally posted by @adityatelange in #974 (comment)

[adityatelange]

Image isn't aligned properly

can you add svg to existing css rules to fit this in?

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication