Fix HAML in profiles/gpg_keys/_key.html.haml

What does this MR do?

Fixs HAML in profiles/gpg_keys/_key.html.haml simply to comply Layout/SpaceAfterColon and Layout/SpaceInsideHashLiteralBraces in HAML-Lint.

Part of #326884 (closed) (and #23855)

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have not included a changelog entry because ~"technical debt" .
• Code review guidelines
• Style guides
• Separation of EE specific content