Add networking benchmarks for libp2p (#6077)

# Description

Implemented benchmarks for Notifications and RequestResponse protocols
with libp2p implementation. These benchmarks allow us to monitor
regressions and implement fixes before they are observed in real chain.
In the future, they can be used for targeted optimizations of litep2p
compared to libp2p.

Part of https://github.com/paritytech/polkadot-sdk/issues/5220

Next steps:
- Add benchmarks for litep2p implementation
- Optimize load to get better results
- Add benchmarks to CI to catch regressions



## Integration

Benchmarks don't affect downstream projects.

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Co-authored-by: alvicsam <[email protected]>
Co-authored-by: GitHub Action <[email protected]>