Mistake in documentation: misnamed variable

[XavierChanth]

The sink variable is called encryptedSink on line 351.

cryptography/cryptography/lib/src/cryptography/cipher.dart

Lines 343 to 354 in 4ba46dc

	/// final sink = encryptedFile.openWrite();
	/// try {
	/// final clearTextStream = file.openRead();
	/// final encryptedStream = state.encryptStream(
	/// clearTextStream,
	/// secretKey: secretKey,
	/// nonce: nonce,
	/// );
	/// await encryptedSink.addStream(encryptedStream);
	/// } finally {
	/// sink.close();
	/// }