update sample tests, fix Java tests #835

	name: Java Client (Echo API) JDK8

	on:
	push:
	paths:
	- samples/client/echo_api/java/apache-httpclient/**
	- samples/client/echo_api/java/feign-gson/**
	- samples/client/echo_api/java/okhttp-gson/**
	- samples/client/echo_api/java/resttemplate/**
	- samples/client/echo_api/java/resteasy/**
	pull_request:
	paths:
	- samples/client/echo_api/java/apache-httpclient/**
	- samples/client/echo_api/java/feign-gson/**
	- samples/client/echo_api/java/okhttp-gson/**
	- samples/client/echo_api/java/resteasy/**
	jobs:
	build:
	name: Build Java Client JDK8
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	sample:
	# clients
	- samples/client/echo_api/java/apache-httpclient
	- samples/client/echo_api/java/feign-gson
	- samples/client/echo_api/java/okhttp-gson
	- samples/client/echo_api/java/resttemplate
	- samples/client/echo_api/java/resteasy
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-java@v4
	with:
	distribution: 'temurin'
	java-version: 8
	- name: Cache maven dependencies
	uses: actions/cache@v4
	env:
	cache-name: maven-repository
	with:
	path: \|
	~/.m2
	key: ${{ runner.os }}-${{ github.job }}-${{ env.cache-name }}-${{ hashFiles('**/pom.xml') }}
	- name: Setup node.js
	uses: actions/setup-node@v4
	- name: Run echo server
	run: \|
	git clone https://github.com/wing328/http-echo-server -b openapi-generator-test-server
	(cd http-echo-server && npm install && npm start &)
	- name: Build
	working-directory: ${{ matrix.sample }}
	run: mvn clean package --no-transfer-progress

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