Update Rust crate serde_json to v1.0.121

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
serde_json	dependencies	patch	1.0.120 -> 1.0.121

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Release Notes

serde-rs/json (serde_json)

### [`v1.0.121`](https://togithub.com/serde-rs/json/releases/tag/v1.0.121) [Compare Source](https://togithub.com/serde-rs/json/compare/v1.0.120...v1.0.121) - Optimize position search in error path ([#​1160](https://togithub.com/serde-rs/json/issues/1160), thanks [@​purplesyringa](https://togithub.com/purplesyringa))

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Configuration

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