Add mastodon logo to sprites as social icon

Purpose

Adds the mastodon icon to be used as a social icon sprite. Intended to be used on User Profile page.

SVG retrieved directly from https://joinmastodon.org/branding, opened in inkscape and resized to 16x16 (Happy for someone with figma to provide a better file content)

Screenshots

Checklist

For a new icon and/or illustration:

• Link to related design issue:
• If this adds an icon ensure that it follows the new icon checklists.
• If this adds an illustration ensure that it follows the new illustration checklists.

For third-party trademarks:

• If this adds or updates an icon or illustration that includes a third-party trademark, ensure that it follows the process for adding third-party trademarks to GitLab.
  • See gitlab-com/legal-and-compliance#1372