feat(`forge script`): add `--gas-price-multiplier`

[409H]

Component

Forge

Describe the feature you would like

When running forge script script/deploy.s.sol and specifying the gas params, either with -g or --gas-price, the output of the simulation (running without --broadcast) shows the estimated gas price of the current block, not what was specified with the cli params and can be confusing.

As per the docs, supplying -g will multiply the estimated gas by some number.

If gas price is 65 gwei, and we want to deploy with 6 gwei, we could specify -g 10

Current avg gas price: 65 gwei Call: forge script script/deploy.s.sol:DeployScript -g 10 --rpc-url https://cloudflare-eth.com/

However, in doing so, the output still specifies the 65 gwei. Interpretation of the output could be that we will deploy with 65 gwei gas price.

## Setting up 1 EVM.

==========================

Chain 1

Estimated gas price: 64.375837984 gwei

Estimated total gas used for script: 15627

Estimated amount required: 0.001006001220175968 ETH

We can confirm the estimated amount required is correct and uses what we specify with -g by calling the same exec with -g 1000.

Current avg gas price: 65 gwei Call: forge script script/deploy.s.sol:DeployScript -g 1000 --rpc-url https://cloudflare-eth.com/

## Setting up 1 EVM.

==========================

Chain 1

Estimated gas price: 64.834925182 gwei

Estimated total gas used for script: 1562760

Estimated amount required: 0.10132142767742232 ETH

It seems to be that Estimated gas price: is not overridden with what we specify in the args but instead of always the gas price of the current block.

Ask:

In the output, either;

• relabel Estimated gas price: to what we specify (in the case of -g 10, it should read Estimated gas price: 6.4834925182 gwei)
• relabel Estimated gas price: to something more accurate such as Block gas price and then a new line item with Broadcasting with gas price: if the user specifies a gas price with -g or --gas-price.

Additional context

No response