chore: fix some typos in comments

[coveralls]

Pull Request Test Coverage Report for Build 8641298728

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.02%) to 56.886%

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Files with Coverage Reduction	New Missed Lines	%
mempool/mempool.go	1	66.84%
<!--	Total:	1		-->

Totals
Change from base Build 8636847188:	0.02%
Covered Lines:	29456
Relevant Lines:	51781

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💛 - Coveralls

[SulaimanAminuBarkindo]

LGTM 🎉

[oftenoccur]

LGTM 🎉

Anything need I to do? If have, Please feel free to tell me.