Remove deprecated warnings from <autogenerated> code

[ironcev]

#6944 extended deprecation checks across additional expressions. This now causes <autogenerated> code for AbiEncode/Decode to generate warnings:

warning
 --> <autogenerated>:4:21
  |
2 |                 #[allow(dead_code)]
3 |                 fn abi_decode(ref mut buffer: BufferReader) -> Self {
4 |                     Self { a: buffer.decode::<u64>(), }
  |                     ---- deprecated struct: Use "NonDeprecatedStruct" instead.
5 |                 }
6 |             }
  |
____

warning
 --> <autogenerated>:4:39
  |
2 |                 #[allow(dead_code)]
3 |                 fn abi_encode(self, buffer: Buffer) -> Buffer {
4 |                     let buffer = self.deprecated_field.abi_encode(buffer);
  |                                       ---------------- deprecated struct field