Symfony integration with Flysystem bundle

[maxhelias]

Hello Azure-OSS team! 👋

I'm a collaborator on the thephpleague/flysystem-bundle project, and I wanted to reach out regarding an opportunity for your Azure Storage Flysystem adapter.
I recently worked on a significant improvement (PR #186) that opens up the adapter builder system, allowing third-party adapter maintainers to provide their own Symfony integration through the flysystem bundle.

What this means:
Instead of requiring Symfony users to manually configure your adapter in their applications, you can now ship an "adapter builder" class with your package (or in a bridge package like the Laravel one). This would allow users to simply configure your adapter through our bundle configuration without writing any boilerplate code.

You'd need to:

1. Create an adapter builder class that implements our interface
2. Register it in Symfony
3. The flysystem-bundle will use it

The documentation and examples for implementing your own adapter builder are available in my fork (pending merge) : https://github.com/maxhelias/flysystem-bundle/blob/rfc-custom-adapter/docs/5-creating-a-custom-adapter.md#creating-a-custom-adapter-builder-advanced

If you're interested or have any questions about the implementation, feel free to reach out. I'd be happy to help or review a PR if you decide to add this integration.

Best regards!

[maxhelias]

In addition, @jonag had already attempted direct integration into the bundle here: thephpleague/flysystem-bundle#181

[cancan101]

Would be great to see this PR merged since thephpleague/flysystem is already recommending this library: thephpleague/flysystem#1860