Injected Adapter can't access Context from parent

[TyrianOtter]

When an adapter is injected, it doesn't get its provider updated from its new parent, so it can't access the context it should, as see in the following:

from refiners.fluxion.adapters.adapter import Adapter
from refiners.fluxion.context import Contexts
import refiners.fluxion.layers as fl

class P(fl.Chain):
    def init_context(self) -> Contexts:
        return {'foo': {'bar': None}}

class A(fl.Chain, Adapter[fl.Chain]):
    def __init__(self, target: fl.Chain):
        with self.setup_adapter(target):
            super().__init__(
                fl.Lambda(lambda: 1),
                fl.SetContext('foo', 'bar'),
            )

    def inject(self, parent: fl.Chain | None = None):
        x = super().inject(parent)
        return x

m = P(
    fl.Chain(
        fl.Lambda(lambda: 1),
        fl.SetContext('foo', 'bar'),
    ),
    fl.UseContext('foo', 'bar'),
)
c, parent = next(m.walk(fl.Chain))

m() # no error
A(c).inject(parent)
# m._register_provider() # uncommenting this stops the next line's error
m() # error: "Context foo not found."

[catwell]

Fixed by #457 - thanks for the report!