The Görli testnet currently used by Threshold/Keep for development purposes is
planned to become deprecated with the end of year 2023. The testnet that is
planned to replace it is called
[Holešky](https://github.com/eth-clients/holesky), however it's not yet
available - it's planned it will become widely accessible on Oct 1, 2023
([source](https://everstake.one/blog/new-ethereum-testnet-holesky-all-you-need-to-know-now)).
Switching our infrastructure to support new testnet is quite time consuming, so
moving directly from Görli to Holešky may be quite risky, especially if there
would be some delays in the date of Holešky genesis (not meeting the planned
timelines is not a rare occurrence in the Ethereum space). As a solution, we
decided to switch first to another testnet that is currently live - Sepolia.
This testnet's EOL is planned for 2026, which gives us plenty of time to move to
Holešky before Sepolia gets deprecated.

There is no scenario were we wouldn't need to provide an `environment` when
manually triggering the workflow run.

We don't need to differenciate between Sepolia and Goerli secrets storing
private keys of the deployers - in both cases we're using the same deployer
address.

We've been using the same account to deploy Keep and Threshold contracts
(both on Goerli and Sepolia).

Without the waiting, the verification of contracts on Etherscan was sometimes
failing with errors like these:
```
NomicLabsHardhatPluginError: Failed to send contract verification request.
Endpoint URL: https://api-sepolia.etherscan.io/api
Reason: The Etherscan API responded that the address
0xAdF78eb37FDE0F3CbF59d11F0DF54b1170a3937b does not have bytecode.
This can happen if the contract was recently deployed and this fact hasn't
propagated to the backend yet.
Try waiting for a minute before verifying your contract. If you are invoking
this from a script, try to wait for five confirmations of your contract
deployment transaction before running the verification subtask.
```
Despite the suggestion to wait 5 confirmation, it seems 2 are enough for us (we
can always increase that number if we find cases where it isn't enough).

The name must be in line with the Hardhat config.

The variable is not needed, it's not used anywhere.