submodule - ssh url must not be converted to HTTPS

[sanjivpurohit]

Due to security reasons, key is already present on the self-hosted server.
When submodules are set to true without ssh-key, ssh url are converted to https, which would prompt the user on the self-hosted server to open a browser and authenticate.

The user has decided to add submodules as ssh since they want to use the keys.
If it required to convert, can we please add a third value to submodules as "ssh-recursive"
OR
add an empty ssh-key:'' to use the local git config ssh key.

[ericsciple]

Unfortunately the current behavior solved a common friction point for many users. You may need to add a run command to script the submodule checkout.