Merge remote-tracking branch 'origin/4.3.x' into 5.0.x

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

@@ -10,7 +10,7 @@ buildscript {
     ext.kotlin_version = '1.3.61'
 
     repositories {
-        mavenCentral()
+        maven { url "https://repo1.maven.org/maven2" }
     }
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
@@ -20,7 +20,7 @@ buildscript {
 apply plugin: 'kotlin'
 
 repositories {
-    mavenCentral()
+    maven { url "https://repo1.maven.org/maven2" }
 }
 
 test {

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

@@ -172,6 +172,12 @@ open class ApiClient(val baseUrl: String) {
     }
 
     protected inline fun <reified T: Any> parseDateToQueryString(value : T): String {
-        return value.toString()
+        /*
+        .replace("\"", "") converts the json object string to an actual string for the query parameter.
+        The moshi or gson adapter allows a more generic solution instead of trying to use a native
+        formatter. It also easily allows to provide a simple way to define a custom date format pattern
+        inside a gson/moshi adapter.
+        */
+        return Serializer.moshi.adapter(T::class.java).toJson(value).replace("\"", "")
     }
 }