standardize rpc response for contract revert

[shunjizhan]

Change

• standardized rpc response when there is revert data, now hardhat matchers works out of box. Revert msg should look like this for evm contract revert

{
      code: -32603,
      data?: '0x hex revert data',
      message?: 'human readable revert data',
    }

• removed old mandala endpoint usage
• removed unused file

Test

removed matcher override from hardhat tutorials, and it's compatible with current RPCs

AcalaNetwork/hardhat-tutorials#102