Remove unnecessary while in SocketIO.readinto

[sc07kvm]

These changes remove unnecessary while left over from the commit 6e6c59b:

while True:
    try:
        return self._sock.recv_into(b)
    except timeout:
        self._timeout_occurred = True
        raise
    except InterruptedError:  // <---------- removed
        continue              // <---------- removed
    except error as e:
        if e.args[0] in _blocking_errnos:
            return None
        raise

-->

while True:
    try:
        return self._sock.recv_into(b)
    except timeout:
        self._timeout_occurred = True
        raise
    except error as e:
        if e.args[0] in _blocking_errnos:
            return None
        raise

[ghost]

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[bedevere-app]

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If this change has little impact on Python users, wait for a maintainer to apply the skip news label instead.

[serhiy-storchaka]

Thank you for your contribution @sc07kvm.