Rodi

- Add the possibility to specify the `ActivationScope` class when instantiating
the `Container` or the `Services` object. This class will be used when
creating scopes. For the issue 55.
- Add an **experimental** class, `TrackingActivationScope` to support nested
scopes transparently, using `contextvars.ContextVar`. For more context, see
the tests `test_nested_scope_1`, `test_nested_scope_2`,
`test_nested_scope_async_1`. For the issue 55.
- Raise a `TypeError` if trying to obtain a service from a disposed scope.
- Remove Python 3.8 from the build matrix, add Python 3.13.
- Handle setuptools warning: _SetuptoolsDeprecationWarning: License classifiers are deprecated_.

- Fixes import for Protocols support regardless of Python version (partially
broken for Python 3.9), by fennel-akunesh

- Adds support for resolving `Protocol` classes even when they don't define an
`__init__` method, by lucas-labs
- Fixes bug in service provider build logic causing singletons to be instantiated
n times when they are registered after its dependant, by lucas-labs
- Changes the "ignore attributes" logic so that if a class variable has already
been initialized externally, rodi doesn't attempt to reinitialize it (and to
also prevent overriding it if the initialized class variable is also a
registered object), by lucas-labs

- Fixes bug in Singleton implementation: stop singleton provider from recreating
objects implementing `__len__`, by [Klavionik](https://github.com/Klavionik).
- Add Python 3.12 and remove Python 3.7 from the build matrix.

- Checks `scoped_services` before resolving from map when in a scope, by [StummeJ](https://github.com/StummeJ).
- Allow getting from scope context without needing to provide scope, by [StummeJ](https://github.com/StummeJ).

- Ignores `ClassVar` properties when resolving dependencies by class notations.
- Marks `rodi` 2 as stable.