Doesn't work if you've connected to gitlab.com before using it with tools.deps.
Workaround: ssh -o 'HostKeyAlgorithms=ssh-rsa' git@gitlab.com
There might be something to do with jsch conflicting versions. https://dev.eclipse.org/mhonarc/lists/jgit-dev/msg03182.html suggests that jsch recently added support for this key.