Show other projects using current project as submodule
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### Problem to solve
We have a project which is used in pretty much every other project as git-submodule. Currently it is a tedious process to check each project if it is using the most recent commit of the master branch of the shared project.
- Is there a way to show other projects using the current project as submodule?
- Maybe even a way to see if the other projects are using an old commit of the shared project?
- Maybe also a button to create a commit updating the shared submodule in the other project
### Further details
### Proposal
- Add a page to see a list of projects using the current project as a submodule
- Add an indicator if the commit checked out by the other project is older than the current master
- Add a button to create a commit in the other project to update the git-submodule
### What does success look like, and how can we measure that?
A page to see a list of other projects using the current project as a git-submodule, and maybe even if the other project uses an old version
### Links / references
issue