Deploy cross-chain projects on Sepolia, cleanup Goerli

[michalinacienciala]

With the end of 2023 Goerli testnet officially became deprecated (although it's nod dead completely, as there are still plenty active validators there). Projects using the testnet were advised to switch to using Sepolia or newly started Holesky testnet.

We've decided to move our config to Sepolia (as it was integrated into more projects we use than Holesky). In #150 we identified the tasks needed for the Goerli -> Sepolia migration and we've executed everything that wasn't blocked due to external factors. As the main objective of that task was fulfilled (we moved the crucial components to Sepolia) and task was becoming hard to manage due to many subtasks, we decided to close that one and create a new one, just for the outstanding/blocked tasks. The main work blocked at the moment is deployment of the cross-chain projects due to Wormhole / Bridge Portal not supporting some L2 testnet chains. Also some of the Goerli cleanup tasks were left for later and we also have some PRs that are ready for review, but not merged yet. We list all those outstanding tasks below.

Cross-chain deployments:

• Configure and deploy @keep-network/tbtc-v2-base on Base Sepolia - Add Sepolia / Base Sepolia support for Base cross-chain keep-network/tbtc-v2#742 (blocked by Bridge Portal not supporting Base Sepolia target network)
• Configure and deploy @keep-network/tbtc-v2-arbitrum on Arbitrum Sepolia - Add Sepolia / Arbitrum Sepolia support for Arbitrum cross-chain keep-network/tbtc-v2#753 (blocked by Bridge Portal not supporting Arbitrum Sepolia target network)
• Configure and deploy @keep-network/tbtc-v2-optimism on Optimism Sepolia - Add Sepolia / Optimism Sepolia support for Optimism cross-chain keep-network/tbtc-v2#752 (blocked by Bridge Portal not supporting Optimism Sepolia target network)
• Configure and deploy @keep-network/tbtc-v2-polygon on Amoy - Add Sepolia support for Polygon cross-chain keep-network/tbtc-v2#751 (blocked by Wormhole and Bridge Portal not supporting Amoy)
• Update Wormhole gateway mappings between the projects (blocked by the above tasks)

Cleanup:

• Remove support for Goerli testnet keep-network/keep-core#3746
• Remove support for Goerli testnet #160
• Remove support for Goerli testnet keep-network/keep-common#119
• Remove support for Goerli testnet keep-network/tbtc-v2#755
• Remove support for Goerli testnet token-dashboard#670
• Remove Goerli-ralated configs from the cross-chain projects - Remove support for Goerli testnet keep-network/tbtc-v2#790
• Remove the Goerli-related GH secrets
• Double check that mentions of Goerli in documentation were removed - https://app.gitbook.com/o/R2meumXNNad4y1B10iL7/s/WosjlL4zUGUMlcMfuSAp/~/diff/~/changes/413/
• Deprecate goerli-related NPM packages (we can also do a cleanup of other obsolete packages)
• Get rid of the Goerli-based testnet dApp and domain
• Remove the Goerli-based deployment from Bitcoin on Base CI - Switch CI to Sepolia bitcoin-on-base#39

Other:

• Adjust optimistic-minting's integration tests for Sepolia contracts