[Kotlin] Fix default values (#17937)

* Fixed invalid extraction of response body in kotlin-client jvm-spring-*

* Generated echo-api for kotlin-jvm-spring-3-restclient

* Specific echo-api for Kotlin without allOf/anyOf

* Specific echo-api for Kotlin without allOf/anyOf

* Generated all samples

* Added kotlin-jvm-spring-3-restclient sample to workflow

* Fixed syntax problem

* [kotlin] Fixed multiple problems with default values

* [kotlin] Removed old commented code

* [kotlin] Generated new samples after merge with master

* [kotlin] ensure-up-to-date

samples/client/echo_api/kotlin-jvm-spring-3-webclient/build.gradle

@@ -0,0 +1,68 @@
+group 'org.openapitools'
+version '1.0.0'
+
+wrapper {
+    gradleVersion = '7.5'
+    distributionUrl = "https://services.gradle.org/distributions/gradle-$gradleVersion-all.zip"
+}
+
+buildscript {
+    ext.kotlin_version = '1.8.10'
+    ext.spring_boot_version = "3.2.0"
+    ext.spotless_version = "6.13.0"
+
+    repositories {
+        maven { url "https://repo1.maven.org/maven2" }
+    }
+    dependencies {
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath "com.diffplug.spotless:spotless-plugin-gradle:$spotless_version"
+    }
+}
+
+apply plugin: 'kotlin'
+apply plugin: 'maven-publish'
+apply plugin: 'com.diffplug.spotless'
+
+repositories {
+    maven { url "https://repo1.maven.org/maven2" }
+}
+
+// Use spotless plugin to automatically format code, remove unused import, etc
+// To apply changes directly to the file, run `gradlew spotlessApply`
+// Ref: https://github.com/diffplug/spotless/tree/main/plugin-gradle
+spotless {
+    // comment out below to run spotless as part of the `check` task
+    enforceCheck false
+
+    format 'misc', {
+        // define the files (e.g. '*.gradle', '*.md') to apply `misc` to
+        target '.gitignore'
+
+        // define the steps to apply to those files
+        trimTrailingWhitespace()
+        indentWithSpaces() // Takes an integer argument if you don't like 4
+        endWithNewline()
+    }
+    kotlin {
+        ktfmt()
+    }
+}
+
+test {
+    useJUnitPlatform()
+}
+
+kotlin {
+    jvmToolchain {
+        languageVersion.set(JavaLanguageVersion.of(17))
+    }
+}
+dependencies {
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
+    implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
+    implementation "com.fasterxml.jackson.module:jackson-module-kotlin:2.14.3"
+    implementation "com.fasterxml.jackson.datatype:jackson-datatype-jsr310:2.14.3"
+    implementation "org.springframework.boot:spring-boot-starter-web:$spring_boot_version"
+    testImplementation "io.kotlintest:kotlintest-runner-junit5:3.4.2"
+}