Upgrade framework

vendor/psr/container/README.md

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+Container interface
+==============
+
+This repository holds all interfaces related to [PSR-11 (Container Interface)][psr-url].
+
+Note that this is not a Container implementation of its own. It is merely abstractions that describe the components of a Dependency Injection Container.
+
+The installable [package][package-url] and [implementations][implementation-url] are listed on Packagist.
+
+[psr-url]: https://www.php-fig.org/psr/psr-11/
+[package-url]: https://packagist.org/packages/psr/container
+[implementation-url]: https://packagist.org/providers/psr/container-implementation
+