[Kotlin Server] Remove setting Kotlin serialization flag to true #5

	name: Samples Kotlin server (jdk21)

	on:
	push:
	paths:
	- 'samples/server/petstore/kotlin-server/**'
	- 'samples/server/petstore/kotlin-server-required-and-nullable-properties/**'
	pull_request:
	paths:
	- 'samples/server/petstore/kotlin-server/**'
	- 'samples/server/petstore/kotlin-server-required-and-nullable-properties/**'

	env:
	GRADLE_VERSION: '8.10'

	jobs:
	build:
	name: Build Kotlin server (jdk21)
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	sample:
	- samples/server/petstore/kotlin-server/javalin-6
	- samples/server/petstore/kotlin-server/ktor
	- samples/server/petstore/kotlin-server-required-and-nullable-properties
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-java@v4
	with:
	distribution: 'temurin'
	java-version: 21
	- name: Cache maven dependencies
	uses: actions/cache@v4
	env:
	cache-name: maven-repository
	with:
	path: \|
	~/.gradle
	key: ${{ runner.os }}-${{ github.job }}-${{ env.cache-name }}-${{ hashFiles('**/pom.xml') }}
	- name: Install Gradle wrapper
	uses: eskatos/gradle-command-action@v3
	with:
	gradle-version: ${{ env.GRADLE_VERSION }}
	build-root-directory: ${{ matrix.sample }}
	arguments: wrapper
	- name: Build
	working-directory: ${{ matrix.sample }}
	run: ./gradlew build -x test

Provide feedback