Plumbing to increase pvf workers configuration based on chain id (#4252)

Part of https://github.com/paritytech/polkadot-sdk/issues/4126 we want
to safely increase the execute_workers_max_num gradually from chain to
chain and assess if there are any negative impacts.

This PR performs the necessary plumbing to be able to increase it based
on the chain id, it increase the number of execution workers from 2 to 4
on test network but lives kusama and polkadot unchanged until we gather
more data.

---------

Signed-off-by: Alexandru Gheorghe <alexandru.gheorghe@parity.io>

polkadot/cli/src/cli.rs

@@ -131,6 +131,23 @@ pub struct RunCmd {
 	#[arg(long, value_name = "PATH")]
 	pub workers_path: Option<PathBuf>,
 
+	/// Override the maximum number of pvf execute workers.
+	///
+	///  **Dangerous!** Do not touch unless explicitly advised to.
+	#[arg(long)]
+	pub execute_workers_max_num: Option<usize>,
+	/// Override the maximum number of pvf workers that can be spawned in the pvf prepare
+	/// pool for tasks with the priority below critical.
+	///
+	///  **Dangerous!** Do not touch unless explicitly advised to.
+
+	#[arg(long)]
+	pub prepare_workers_soft_max_num: Option<usize>,
+	/// Override the absolute number of pvf workers that can be spawned in the pvf prepare pool.
+	///
+	///  **Dangerous!** Do not touch unless explicitly advised to.
+	#[arg(long)]
+	pub prepare_workers_hard_max_num: Option<usize>,
 	/// TESTING ONLY: disable the version check between nodes and workers.
 	#[arg(long, hide = true)]
 	pub disable_worker_version_check: bool,

polkadot/cli/src/command.rs

@@ -253,6 +253,9 @@ where
 					.overseer_channel_capacity_override,
 				malus_finality_delay: maybe_malus_finality_delay,
 				hwbench,
+				execute_workers_max_num: cli.run.execute_workers_max_num,
+				prepare_workers_hard_max_num: cli.run.prepare_workers_hard_max_num,
+				prepare_workers_soft_max_num: cli.run.prepare_workers_soft_max_num,
 			},
 		)
 		.map(|full| full.task_manager)?;