[deps]: Update Xamarin.Kotlin.StdLib to v2

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
Xamarin.Kotlin.StdLib (source)	1.9.10.1 -> 2.0.21.1

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[bitwarden-bot]

Internal tracking:

• ID: PM-9988
• Link: https://bitwarden.atlassian.net/browse/PM-9988