fix(deps): update kotlin monorepo to v1.9.20

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.jetbrains.kotlin:kotlin-serialization (source)	1.9.10 -> 1.9.20
org.jetbrains.kotlin:kotlin-gradle-plugin (source)	1.9.10 -> 1.9.20

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