Update ERC-2135: fix some typos

[rustrover]

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[eip-review-bot]

File ERCS/erc-2135.md

Requires 1 more reviewers from @xinbenlv
Requires 1 more reviewers from @axic, @gcolvin, @lightclient

File ERCS/erc-5252.md

Requires 1 more reviewers from @hskang9, @smuxx

File ERCS/erc-5023.md

Requires 1 more reviewers from @axic, @gcolvin, @lightclient

File ERCS/erc-6105.md

Requires 1 more reviewers from @axic, @gcolvin, @lightclient

[h4l]

Change to ERCS/erc-6120.md is fine.

[yaruno]

erc-5023 look ok

[aaronisme]

erc-4527 looks fine