Pulling submodules from github/slablab requires to setup an ssh key with github and a github login. Since everything is public when pulling a repository can the submodules use https URLs to eliminate the need for github user setup
Example in atlas-rd53-daq/.git/config
[core]
repositoryformatversion = 0
filemode = true
bare = false
logallrefupdates = true
[remote "origin"]
url = https://github.com/slaclab/atlas-rd53-daq.git
fetch = +refs/heads/:refs/remotes/origin/
[branch "master"]
remote = origin
merge = refs/heads/master
[submodule "firmware/submodules/axi-pcie-core"]
url = https://github.com/slaclab/axi-pcie-core
[submodule "firmware/submodules/levkurilenko/aurora_rx"]
url = https://bitbucket.org/levkurilenko/aurora_rx
[submodule "firmware/submodules/levkurilenko/cern_work"]
url = https://bitbucket.org/levkurilenko/cern_work
[submodule "firmware/submodules/rce-gen3-fw-lib"]
url = https://github.com/slaclab/rce-gen3-fw-lib
[submodule "firmware/submodules/ruckus"]
url = https://github.com/slaclab/ruckus
[submodule "firmware/submodules/surf"]
url = https://github.com/slaclab/surf