Investigate the test in `peer_test.rs`

[lemmih]

Issue summary

We have a module that contains a single test. This module is not used by the crate and the test is therefore not run. We should investigate what to do about this. Possible options:

• Use the module such that the test is run.
• Move the test to the tests/ folder. This can only be done if the test doesn't depend on anything private from the crate.
• Remove the test. Maybe the test isn't relevant anymore and should be removed.

File in question: https://github.com/ChainSafe/forest/blob/main/blockchain/chain_sync/src/sync/peer_test.rs

Other information and links