Missing R8 rules for OkHttp

[viktor-aleck]

Describe the bug
Release build (task minifyReleaseWithR8) is failing with missing class error

ERROR: R8: Missing class okhttp3.internal.Util (referenced from: void io.livekit.android.util.OkHttpCallExtKt$executeAsync$2$2$onResponse$1.invoke(java.lang.Throwable))
> Task :app:minifyReleaseWithR8 FAILED

To Reproduce
Add LiveKit SDK + OkHttp dependencies and execute minifyReleaseWithR8 gradle task

Versions:

• LiveKit SDK version: 2.21.0
• OkHttp version: 5.2.1