Decouple the application from the global state

[jkrzefski]

This will decouple the application from the global state of its surrounding infrastructure using the Symfony Runtime Component. In his talk at Symfony World 2021 Tobias Nyholm made some compelling arguments for this change.

[shyim]

I don't see any benefit here when the actual application does not run on the other runtimes.

[shopwareBot]

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[NiklasLimberg]

Hi @jkrzefski, I rebased it and resolved the merge conflict but it seems to break the pipeline internally so this could take a while.

[NiklasLimberg]

Hi @jkrzefski, I rebased/merged this incorectly and it took me a few weeks to notice. I fixed it, but now it has to wait for the next release. If you want to know why ask @shyim

[shyim]

Hey,

We will not merge this until 6.5 as it could be breaking. BUT! it's already merged for the new template based on Symfony Flex: https://github.com/shopware/recipes/commit/ee809d1be8639f96a4c6048ede215b7e2b993743

To set up a Project using Flex use composer create-project shopware/production:dev-flex <project-name>

Thanks!