feat(protocol): Remove non-working FoundryRandom and implement a custom one

[adaki2004]

FoundryRandom's codebase does not provide us with random variables. (Maybe it's on my machine ((!?)).

You can test it out by putting this debug logging into the current code you have at major_protocol_upgrade_alpha3 's TaikoL1.sim.sol file: (somewhere after the random generation of the respective variables):

            console2.log("-----------------------------");
            console2.log("gasLimit:", gasLimit);
            console2.log("-----------------------------");
            console2.log("gasUsed:", gasUsed);
            console2.log("-----------------------------");
            console2.log("txListSize:", txListSize);
            console2.log("-----------------------------");
            console2.log("blockHash:");
            console2.logBytes32(blockHash);
            console2.log("-----------------------------");
            console2.log("signalRoot:");
            console2.logBytes32(signalRoot);

This branch and PR are solving the problem with a custom randomGenerator with randomNum+salt. (Obviously semi-random, but seems to be working.)

[dantaik]

please also remove it from .gitmodules

[dantaik]