fix test in smart-contract-example

[tuky191]

Hey,

was trying to follow the deploy-and-test-your-dapp-locally

but when running the npx hardhat test --network localnet i just got following error.

  ChipToken
    mint
      1) "before each" hook for "should mint 1000 chips for PLAYER ONE"


  0 passing (66ms)
  1 failing

  1) ChipToken
       "before each" hook for "should mint 1000 chips for PLAYER ONE":
     TypeError: this.chips.deployed is not a function
      at Context.<anonymous> (test/ChipToken.js:11:22)
      at processTicksAndRejections (node:internal/process/task_queues:95:5)

deployed() is no longer in use and is replaced with waitForDeployment()

after changing, the test is passing

  ChipToken
    mint
      ✔ should mint 1000 chips for PLAYER ONE (13047ms)


  1 passing (21s)