Remove ExperimentalOkHttpApi references (#8908)

Author: yschimke

build.gradle.kts

@@ -247,24 +247,7 @@ subprojects {
   }
 }
 
-// Opt-in to @ExperimentalOkHttpApi everywhere.
 subprojects {
-  plugins.withId("org.jetbrains.kotlin.jvm") {
-    kotlinExtension.sourceSets.configureEach {
-      languageSettings.optIn("okhttp3.ExperimentalOkHttpApi")
-    }
-  }
-  plugins.withId("org.jetbrains.kotlin.multiplatform") {
-    kotlinExtension.sourceSets.configureEach {
-      languageSettings.optIn("okhttp3.ExperimentalOkHttpApi")
-    }
-  }
-  plugins.withId("org.jetbrains.kotlin.android") {
-    kotlinExtension.sourceSets.configureEach {
-      languageSettings.optIn("okhttp3.ExperimentalOkHttpApi")
-    }
-  }
-
   // From https://www.liutikas.net/2025/01/12/Kotlin-Library-Friends.html
 
     // Create configurations we can use to track friend libraries