Add tests to contracts

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Tasks

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1. Add tests to the CCM counter example #132
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2. Add tests to the CCM message example #133
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3. Add tests to the CCM value example #134
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4. Add tests to the CCM warriors example #135
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5. Add tests to the omnichain swap example #136
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6. Add tests to the omnichain NFT example #137
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7. Add tests to the omnichain value example #138
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8. Add tests to the omnichain staking example #139
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For reference we can use tests from the app contracts repo:

https://github.com/zeta-chain/zetachain/blob/main/packages/zeta-app-contracts/test/MultiChainValue.spec.ts

https://github.com/zeta-chain/zetachain/tree/main/packages/zevm-app-contracts/test

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If we need any reusable code, we can add it to the toolkit.

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There is also an example in this PR: #113