* Parachains source cosmetic changes

- Make `ParaHashAtSource` more generic
- Modify `on_chain_parachain_header` to return `HeaderId`
- Shortening variable names

Signed-off-by: Serban Iorga <[email protected]>

* Change ParachainsSource::max_head_id type

Change ParachainsSource::max_head_id to Arc<Mutex<NoopOption>>

Signed-off-by: Serban Iorga <[email protected]>

* code review changes

* add another condition to the reject-obsolete-parachain-heads extension

* add tracing to obsolete-tx-extensions

* fix tests

* extension_rejects_header_from_new_relay_block_with_same_hash

* fmt

* fix benchmarks

* parachain loop metrics

* some fixes

* mini refactoring

* add tests

* added parachains pallet benchmarks

* deduplicate insertion of bridged header

* pruning weight

* fixes

* fix compilation

* add RialtoParachain <> Millau bridge to test deployments

* flush (still not working, but possible fix in comments)

* proper fix

* fixed on-demand parachains relay case: if better relay header is delivered, then we must select para header that may be proved using this relay header

* dashboards

* fmt

* removing debugging code

* more cleanup

fixed on-demand parachains relay case: if better relay header is delivered, then we must select para header that may be proved using this relay header (#1419)

* fix clippy warnings

* try to reenable proper clippy on CI

* fix clippy error

* more Eqs

* ignore clippy::derive-partial-eq-without-eq - clippy seems to be broken now :/