test: stableswap invariant cases

[mrq1911]

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[github-actions]

Crate versions that have been downgraded:

• runtime-integration-tests: v1.52.5 -> v1.49.0
• hydra-dx-math: v10.4.1 -> v10.2.0
• hydradx: v14.5.0 -> v14.4.0
• pallet-circuit-breaker: v1.2.3 -> v1.2.1
• pallet-currencies: v3.3.0 -> v3.2.0
• pallet-dca: v1.9.5 -> v1.9.4
• pallet-dispatcher: v1.2.0 -> v1.1.1
• pallet-duster: v3.3.2 -> v3.2.9
• pallet-dynamic-evm-fee: v1.1.1 -> v1.0.7
• pallet-dynamic-fees: v4.0.0 -> v3.0.1
• pallet-hsm: v1.3.1 -> v1.1.3
• pallet-liquidation: v1.4.2 -> v1.4.0
• pallet-liquidity-mining: v4.4.8 -> v4.4.7
• pallet-otc: v2.1.8 -> v2.1.7
• pallet-otc-settlements: v1.1.10 -> v1.1.9
• pallet-parameters: v1.0.2 -> v1.0.1
• pallet-route-executor: v2.10.2 -> v2.10.1
• pallet-stableswap: v5.5.1 -> v5.4.3
• pallet-transaction-multi-payment: v10.1.7 -> v10.1.6
• primitives: v6.1.3 -> v6.1.2
• runtime-mock: v1.0.9 -> v1.0.6
• hydradx-adapters: v1.9.2 -> v1.9.0
• hydradx-runtime: v351.0.0 -> v336.0.0
• scraper: v1.3.2 -> v1.3.1
• hydradx-traits: v4.2.0 -> v4.0.0

Runtime version has been increased.