Allow .gitlab directory description template to be a submodule
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### Description
At work, we are working with Java, so we have many modules. I've set up [description template](https://docs.gitlab.com/ce/user/project/description_templates.html) for each repository. So, I tried to set up a git repository for all our templates, and then I tried to set up this template repository as a submodule of the Java module repositories, but it didn't work as I expected.
Maybe it is a bad idea. I don't know if it's great to do something like that.
### Proposal
Make description template available in a Gitlab repository using a submodule called `.gitlab`.
### Links / references
I saw these non-related issues which could be great too for the use case. I'm just wondering what's better :thinking_face: :
gitlab-ce#13729
gitlab-ce#30957
gitlab-ce#22310
#### Use cases
For company working with many similar projects like micro-services oriented architecture with one service per repository, it could be great to version description template in another repository and add it as a submodule of these repositories
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I hope I am clear enough. By the way, Gitlab is great ! :smiley:
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### Feature checklist
Make sure these are completed before closing the issue,
with a link to the relevant commit.
- [ ] [Feature assurance](https://about.gitlab.com/handbook/product/#feature-assurance)
- [ ] Documentation
- [ ] Added to [features.yml](https://gitlab.com/gitlab-com/www-gitlab-com/blob/master/data/features.yml)
issue