Error with receive functions

[grallc]

For some reasons, if the ABI contains a receive payable function with no further arguments, instantiating a new Contract will throw an TypeError: Cannot read property 'type' of null error.
The problem seems to be coming from the Fragment from ethersprojects, but can also be fixed in the library.

Can be reproduced by using this ABI:

  const abi = [
    {
        constant: true,
        inputs: [],
        name: 'totalSupply',
        outputs: [
            {
                internalType: 'uint256',
                name: '',
                type: 'uint256'
            }
        ],
        payable: false,
        stateMutability: 'view',
        type: 'function'
    },
    {
      stateMutability: 'payable',
      type: 'receive'
    }
  ]

in the tests.

[roffett]

Met the same issues, fallback() payable throw the same err as well