How to use submodules in a plugin with packer

[AbdelrahmanDwedar]

I'm making a plugin that relies on few other repositories that's open source (also plugins to be exact), and it's better for me to have these repositories as submodules and use in the project. So I was wondering if packer would automatically initialize those submodules or if there's a way to enable that.

If there's none inform me so I'll be adding a line for them to add on installation.

Thanks.