Found by @ggwpez



Fix staking benchmark, error was introduced when migrating to v2:
https://github.com/paritytech/polkadot-sdk/pull/6025

Also disable flaky tests similar to
https://github.com/paritytech/polkadot-sdk/pull/6749:
* zombienet-polkadot-functional-0017-sync-backing 
*
zombienet-polkadot-elastic-scaling-0002-elastic-scaling-doesnt-break-parachains

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Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>