✨ Support `watchosSimulatorArm64` Kotlin Native target

[LVMVRQUXL]

📝 Description

We would like to support the watchosSimulatorArm64 Kotlin Native target.

See the targets supported by Kotlin Native for more details about it.

✅ Checklist

• [ ] ✨ Add the target in the Gradle convention plugin for Kotlin Multiplatform.
• [ ] 📝 Add a badge for the new target in the README documentation of the root Gradle project.
• [ ] 📝 Add a badge for the new target in the README documentation of the types-kotlinx-serialization Gradle project.
• [ ] 📝 Update the unreleased changelog for this issue.

[LVMVRQUXL]

We should attach a discussion to this issue before implementing it.

[LVMVRQUXL]

This issue will be resolved by #621.

[LVMVRQUXL]

As of today, watchOS platform is not stable yet in Kotlin Multiplatform.