Automate Superchain Registry chain support

[emlautarom1]

Solves #8065

Changes

• Add a superchain.py script to fetch, process and generate Nethermind compatible files for all OP Sperchain chains (see https://github.com/ethereum-optimism/superchain-registry)

Types of changes

What types of changes does your code introduce?

• Bugfix (a non-breaking change that fixes an issue)
• New feature (a non-breaking change that adds functionality)
• Breaking change (a change that causes existing functionality not to work as expected)
• Optimization
• Refactoring
• Documentation update
• Build-related changes
• Other: Description

Testing

Requires testing

• Yes
• No

If yes, did you write tests?

• Yes
• No

Notes on testing

Added tests to verify that we're properly decompressing generated ChainSpec files. Some tests were updated to use a new ChainSpecFileLoader that is format-aware of ChainSpec files, thus is able to decompress them if needed.

Documentation

Requires documentation update

• Yes
• No

Requires explanation in Release Notes

• Yes
• No

Once this feature is properly working we need to document that Nethermind now supports all OP Superchain chains, not only a small subset (currently: OP, Base and Worldchain).

Remarks

The generated ChainSpec files are stored in a compressed format due to their excessive size when in .json format. Just like in the Superchain Registry repository (https://github.com/ethereum-optimism/superchain-registry/blob/cb9a0ca8eda1608bf9958137a736fd2c18884fbd/superchain/README.md) we use zstandard as the compression algorithm. This is due to the OP team already figuring out that this is one of the best algorithms for this use case, and also to reduce the required amount of code (our scripts already deal with decompression so might as well compress the resulting artifacts using the same algorithm).

Currently, 45 configs are generated: 28 in Mainnet and 17 in Sepolia.

We're still missing a GitHub action that automatically runs this script either periodically or when the Superchain Registry repository gets updated (the latter being preferable)

[kamilchodola]

@stdevMac Can you take care of checking this and making sure it works accordingly with Sedge? Also add to our CI BUT limit those side chains to trigger once per week.