Integration into the CI will happen in the following diffs. This is to confirm structure of `bitcoinsuite-chronik-client` within `modules`. This is a client module written in Rust for interacting with the Chronik API.
Added `"modules/bitcoinsuite-chronik-client"` to the main Cargo.toml file `bitcoin-abc/Cargo.toml` so that Rust analyser works in `bitcoinsuite-chronik-client`
Made `bytes::Bytes` public so that it can access `Bytes` across files within `bitcoinsuite-chronik-client`.
Testing comments to cover what each test is doing will be put forward in a seperate diff as not part of original source material.