DRAFT PR | simplify interaction with multisig wallets in deployment scripts

[alysiahuggins]

Closes #1838

This PR:

• provides scripts to deploy the FeeContract, LightClient Contract and PlonkVerifier library without OpenZeppelin Defender and without a multisig wallet creating the transaction (thus via an EOA)
• provides scripts to upgrade the FeeContract and LightClient using an EOA to deploy the new implementation contracts and the Safe SDK to create a transaction on the Safe interface so that a Safe multisig wallet can be used to upgrade the proxy contracts as its the owner of these proxies

Key places to review:

• updated README
• updated scripts

How to test this PR:

• Follow the instructions in the README to deploy the contracts above
• Follow the instructions in the README to upgrade the FeeContract and LightClient proxies

Things tested

• deploying the contracts mentioned above using the forge script command
• upgrading the respective proxies using the forge script command

Things not tested

• interacting with functions on the PlonkVerifier library once deployed