doc: Add committer entries for Juraj Lutter <otis>

Steps 1-4 from the Committer's guide:

• Add entries for Juraj Lutter <otis>
• Add GPG key

And while here, also:

• Fix misindentation
• Remove a stray empty line

Reviewed by: osa (mentor)
Approved by: osa (mentor)
Differential Revision: https://reviews.freebsd.org/D27617