Avoid custom/plugins dir is ignored during new project initialization

[amansilla]

This fix solved the following issue: as a developer, I start new shopware based projects with the following behavior:

How to reproduce:

1. git clone [email protected]:shopware/production.git my-new-shopware-project
2. cd my-new-shopware-project && rm -rf .git # because I don't want to keep the whole shopware git history, branches, and so on
3. git init
4. git add custom
5. git status

On branch main

No commits yet

Changes to be committed:
  (use "git rm --cached <file>..." to unstage)
	new file:   custom/static-plugins/.gitkeep

The issue here is that the dir custom/plugins and his .gitkeep are ignored. As consequence other tasks e.g. installing new plugins from the admin panel will fail.

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[amansilla]

@keulinho @shyim What do you think about this?

[shyim]

Hey,

I am closing this as we migrated to Symfony Flex with recipes. So this repository is now empty