Replace provider file content

[markwalet]

In one of my projects I'm enforcing declare(strict_types=1); with a QA rule.

That's how I found out that ServiceProvider::addProviderToBootstrapFile() replaces the whole file. After adding a provider, the strict type declaration was removed from the file and making my QA fail.

This PR improves on this, by only replacing the relevant part of the file (the array part). It does so by using regex. It isn't a perfect solution, but at least everything around the array would stay untouched. Because bootstrap/providers.php normally doesn't contain a lot of other code, I think this is fine for most general use-cases.

[taylorotwell]

Could you maybe exclude this file from your QA rule?

[markwalet]

Oh yes, that's definitely possible. In my specific case I just added the statement back in and it was fine. Not a big problem.

I just thought it would be helpful if adding a provider wouldn't reset the whole file. And because I could do it without changing the api, I thought it would be a useful contribution.