Replace old createStakingPools script with new updated one

[mixplore]

Context

Needed for FE dev: https://github.com/NexusMutual/frontend-react/issues/781

Changes proposed in this pull request

• removed old script for creating staking pools
• added a new mock script for creating 2 staking pools and deposit to each

Test plan

With local deployment running, run HARDHAT_NETWORK=localhost node scripts/mocks/createStakingPools.js.

Checklist

• Rebased the base branch
• Attached corresponding Github issue
• Prefixed the name with the type of change (i.e. feat, chore, test)
• Performed a self-review of my own code
• Followed the style guidelines of this project
• Made corresponding changes to the documentation
• Didn't generate new warnings
• Didn't generate failures on existing tests
• Added tests that prove my fix is effective or that my feature works

Review

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• 🍰 = Nice to have but not essential.
• 💡 = Suggestion or a comment based on personal opinion
• 🔨 = I believe this should be changed.
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• 🚀 = Feedback