[kotlin][client] gson complete integration (#4332)

* [kotlin] update dependencies

* [kotlin][client] complete gson integration

* [kotlin][client] run petstores

* [kotlin][client] fix JsonMediaType and update petstores

* Add kotlin client gson to pom.xml

* Remove org.json dependency

* Try to fix kotlin-gson build

* Add kotlin client nonpublic to pom.xml

* Update samples

* try to fix build

* try to fix build

* try to fix build

* try to fix build

* [kotlin][client] restore libraries version

* [kotlin][client] update kotlin version

* [kotlin][client] update some libraries versions

* [kotlin][client] update some libraries versions

* [kotlin][client] add kotlin-gson and kotlin-nonpublic to CI test suit

* [kotlin][client] update some libraries versions

* try to fix build

* try to fix build

samples/client/petstore/kotlin-string/build.gradle

@@ -7,7 +7,7 @@ wrapper {
 }
 
 buildscript {
-    ext.kotlin_version = '1.3.41'
+    ext.kotlin_version = '1.3.50'
 
     repositories {
         mavenCentral()
@@ -32,6 +32,6 @@ dependencies {
     compile "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
     compile "com.squareup.moshi:moshi-kotlin:1.8.0"
     compile "com.squareup.moshi:moshi-adapters:1.8.0"
-    compile "com.squareup.okhttp3:okhttp:4.2.0"
-    testImplementation "io.kotlintest:kotlintest-runner-junit5:3.1.0"
+    compile "com.squareup.okhttp3:okhttp:4.2.2"
+    testCompile "io.kotlintest:kotlintest-runner-junit5:3.1.0"
 }

samples/client/petstore/kotlin-string/src/main/kotlin/org/openapitools/client/infrastructure/ByteArrayAdapter.kt

@@ -9,4 +9,4 @@ class ByteArrayAdapter {
 
     @FromJson
     fun fromJson(data: String): ByteArray = data.toByteArray()
-}
+}