Add the social icon for Bluesky

[shimoju]

What does this PR change? What problem does it solve?

Add the social icon for Bluesky, is a microblogging social platform.

• This logo is from bluesky-social/atproto-website repo.
  • Unnecessary SVG paths were removed.
• This SVG image is used on the AT Protocol website.

Was the change discussed in an issue or in the Discussions before?

#1376
This Pull Request adds only the Bluesky social icon, not the share icon.

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.

[sonarcloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[adityatelange]

LGTM 👍
Thanks @shimoju!

[shimoju]

Thanks!!