Fix/arg out of range SnapProvider.AddAccountRange

[ak88]

Fixes #7033

Changes

SnapProvider.AddAccountRange will now throw in case of empty account list , and AddAccountRange(AccountRange request, AccountsAndProofs response) will return ExpiredRootHash in case of empty account list.

What types of changes does your code introduce?

• [x] Bugfix (a non-breaking change that fixes an issue)
• [ ] New feature (a non-breaking change that adds functionality)
• [ ] Breaking change (a change that causes existing functionality not to work as expected)
• [ ] Optimization
• [ ] Refactoring
• [ ] Documentation update
• [ ] Build-related changes
• [ ] Other: Description