Problem: eth_getLogs with large block range is slow and cause OOM

[yihuang]

Closes: #281

Solution:

• use the fix in ethermint

👮🏻👮🏻👮🏻 !!!! REFERENCE THE PROBLEM YOUR ARE SOLVING IN THE PR TITLE AND DESCRIBE YOUR SOLUTION HERE !!!! DO NOT FORGET !!!! 👮🏻👮🏻👮🏻

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Thank you for your code, it's appreciated! :)

[yihuang]

https://github.com/crypto-org-chain/ethermint/compare/v0.7.2-cronos-6...v0.7.2-cronos-7?expand=1

[leejw51crypto]

lgtm