Fix parachain-staking benchmarks

[sea212]

What does it do?

Two errors hindered the successful execution of the benchmarks within pallet-parachain-staking.

1. MinSelectedCandiates = 8 for battery station runtime, which is used in dev parachain, is less than num_selected_candidates in dev parachain's GenesisConfig. However, the condition num_selected_candidates >= MinSelectedCandidates must be met.
2. Fix runtime-benchmarks moonbeam-foundation/moonbeam#2227

This PR fixes 1. and updated dependencies from the Moonbeam branch that incorporates 2.

What important points should reviewers know?

Is there something left for follow-up PRs?

What alternative implementations were considered?

Are there relevant PRs or issues?

References

[Chralt98]

The obvious question: I think you did initially use num_selected_candidates = 1, because if we use cargo build and then ./target/debug/zeitgeist --dev --tmp we are usually having only one node instance running. So hopefully the dev configuration still produces blocks.

[sea212]

The obvious question: I think you did initially use num_selected_candidates = 1, because if we use cargo build and then ./target/debug/zeitgeist --dev --tmp we are usually having only one node instance running. So hopefully the dev configuration still produces blocks.

We use the standalone client for one node environments, this parameter only affects the parachain client though.