Add new try-state check invariant for nomination-pools (points >= stake) (#5465)

closes https://github.com/paritytech/polkadot-sdk/issues/5448

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Co-authored-by: Gonçalo Pestana <g6pestana@gmail.com>
Co-authored-by: Ankan <10196091+Ank4n@users.noreply.github.com>