[types] ProposalFunctionInputs type seems outdated - does not match documentation

[bstchow]

Issue

Current ProposalFunctionInputs type does not match API documentation
https://docs.openzeppelin.com/defender/v1/admin-api-reference

type ProposalFunctionInputsArray = (string | boolean)[];
type ProposalFunctionInputs = (
  | string
  | boolean
  | (string | boolean | (string | boolean | (string | boolean | ProposalFunctionInputsArray)[])[])[]
)[];

Fix

#324