[DOC] Add docs on how to clear state

[gagdiez]

Documentation Type

New Documentation

What needs documentation?

While developing a contract, it is very common to need to clear state (i.e. delete all information from the contract) as new updates are pushed to the smart contract

There are some tools to simplify clearing the state, we need to provide them in our documentation

Acceptance Criteria

• Add https://github.com/doriancrutcher/near-clear-state as a tool to our documentation

Resources & References

https://github.com/doriancrutcher/near-clear-state

Priority

🟡 P2 : Documentation Enhancement