fix: Delete unused config files in validium pubdata abstraction

[toni-calvin]

Issues

Merging this PR fixes: #111, #108, #109 and #110

What ❔

Removing era-contracts-lambda submodule as it is no longer necessary. Also removing zksync-config crate from l1-contract-interface as it is not used anymore.
There is also a sql file created in the initialisation that should not be tracked.
Finally there is a nit where empty structs don't need braces so it removes them.

Why ❔

Removing unnecessary imports and repository files.

Description ❕

This pull request aims to streamline the repository by removing the now unnecessary era-contracts-lambda submodule and the zksync-config crate from l1-contract-interface. These changes have been made to clean up the codebase, removing unused dependencies and files.

Expected Behavior ❗

After applying these changes, running the following commands should complete successfully without any issues:

zk
zk clean --all
zk init --validium-mode
zk server

[ilitteri]

LGTM. For next time, even if the changes are minimal, every issue should have its own PR (this is not mandatory btw, it depends on the tasks, in this case it applies)