TotalWeight may exceed MAX_UINT64 in mainchain registration command verification

[shuse2]

Expected behavior

The MAX_UINT64 check should be performed on the result of the addition

Actual behavior

The verify method of the MainchainRegistrationCommand class iterates through the provided list of mainchain validators, summing their BFT weights into the totalWeight variable. If totalWeight exceeds the MAX_UINT64 constant, the loop terminates, and the method returns an error

Steps to reproduce

Link to code

Which version(s) does this affect? (Environment, OS, etc...)

6.0.0-beta.3