[kotlin][client] make kotlinx serialization configurable from outside

Author: 4brunu

modules/openapi-generator/src/main/resources/kotlin-client/jvm-common/infrastructure/Serializer.kt.mustache

@@ -50,7 +50,9 @@ import org.threeten.bp.OffsetDateTime
 {{/threetenbp}}
 import java.util.UUID
 import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonBuilder
 import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.SerializersModuleBuilder
 import java.net.URI
 import java.net.URL
 import java.util.concurrent.atomic.AtomicBoolean

samples/client/petstore/kotlin-json-request-string/src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt

@@ -7,7 +7,9 @@ import java.time.LocalDateTime
 import java.time.OffsetDateTime
 import java.util.UUID
 import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonBuilder
 import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.SerializersModuleBuilder
 import java.net.URI
 import java.net.URL
 import java.util.concurrent.atomic.AtomicBoolean

samples/client/petstore/kotlin-retrofit2-kotlinx_serialization/src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt

@@ -7,7 +7,9 @@ import java.time.LocalDateTime
 import java.time.OffsetDateTime
 import java.util.UUID
 import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonBuilder
 import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.SerializersModuleBuilder
 import java.net.URI
 import java.net.URL
 import java.util.concurrent.atomic.AtomicBoolean

samples/client/petstore/kotlin-uppercase-enum/src/main/kotlin/org/openapitools/client/infrastructure/Serializer.kt

@@ -7,7 +7,9 @@ import java.time.LocalDateTime
 import java.time.OffsetDateTime
 import java.util.UUID
 import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonBuilder
 import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.SerializersModuleBuilder
 import java.net.URI
 import java.net.URL
 import java.util.concurrent.atomic.AtomicBoolean