Fixed some gradle warnings

Author: Daeda88

firebase-common/build.gradle.kts

@@ -80,7 +80,6 @@ kotlin {
                 this.apiVersion = apiVersion
                 this.languageVersion = languageVersion
                 progressiveMode = true
-                optIn("kotlin.Experimental")
                 optIn("kotlinx.coroutines.ExperimentalCoroutinesApi")
                 optIn("kotlinx.serialization.ExperimentalSerializationApi")
                 optIn("kotlinx.serialization.InternalSerializationApi")

firebase-firestore/build.gradle.kts

@@ -86,15 +86,6 @@ kotlin {
         }
     }
 
-    tasks.withType<org.jetbrains.kotlin.gradle.dsl.KotlinCompile<*>> {
-        kotlinOptions.freeCompilerArgs += listOf(
-            "-Xopt-in=kotlin.Experimental",
-            "-Xopt-in=kotlinx.coroutines.ExperimentalCoroutinesApi",
-            "-Xopt-in=kotlinx.serialization.InternalSerializationApi",
-            "-Xopt-in=kotlinx.serialization.ExperimentalSerializationApi"
-        )
-    }
-
     sourceSets {
         all {
             languageSettings.apply {

firebase-functions/build.gradle.kts

@@ -82,14 +82,6 @@ kotlin {
         }
     }
 
-    tasks.withType<org.jetbrains.kotlin.gradle.dsl.KotlinCompile<*>> {
-        kotlinOptions.freeCompilerArgs += listOf(
-            "-Xopt-in=kotlin.Experimental",
-            "-Xopt-in=kotlinx.coroutines.ExperimentalCoroutinesApi",
-            "-Xopt-in=kotlinx.serialization.InternalSerializationApi"
-        )
-    }
-
     sourceSets {
         all {
             languageSettings.apply {