Rename polkadot-parachain to polkadot-parachain-primitives (#1334)

* Rename `polkadot-parachain` to `polkadot-parachain-primitives`

While doing this it also fixes some last `rustdoc` issues and fixes
another Cargo warning related to `pallet-paged-list`.

* Fix compilation

* ".git/.scripts/commands/fmt/fmt.sh"

* Fix XCM docs

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Co-authored-by: command-bot <>

polkadot/node/subsystem-test-helpers/src/lib.rs

@@ -338,7 +338,7 @@ pub fn subsystem_test_harness<M, OverseerFactory, Overseer, TestFactory, Test>(
 	});
 }
 
-/// A forward subsystem that implements [`Subsystem`].
+/// A forward subsystem that implements [`Subsystem`](overseer::Subsystem).
 ///
 /// It forwards all communication from the overseer to the internal message
 /// channel.