man page mentions unknown option --continue

[Moses Moore]

in the git-merge man page, in the "HOW TO RESOLVE CONFLICTS" section, it says

    Use git commit or git merge --continue to seal the deal.

But when I try `git merge --continue` or `git merge --continue $branch` I get

    error: unknown option `continue'

ProblemType: Bug
DistroRelease: Ubuntu 19.10
Package: git 1:2.20.1-2ubuntu1.19.10.1
ProcVersionSignature: Ubuntu 5.3.0-24.26-generic 5.3.10
Uname: Linux 5.3.0-24-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu8.5
Architecture: amd64
CurrentDesktop: KDE
Date: Thu Mar 12 11:27:24 2020
InstallationDate: Installed on 2018-10-30 (498 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
SourcePackage: git
UpgradeStatus: Upgraded to eoan on 2019-11-14 (118 days ago)
mtime.conffile..etc.logrotate.d.apport: 2018-12-13T12:13:33.355709