Updated the readme for opensearch plugin to use date processor in combination with Opensearch sink #9160

	# This workflow will build a Java project with Gradle
	# For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-gradle

	name: Data Prepper Log Analytics Basic Grok End-to-end test with Gradle

	on:
	push:
	branches: [ main ]
	pull_request:
	workflow_dispatch:

	jobs:
	build:
	strategy:
	matrix:
	java: [11, 17, 21, docker]
	test: ['basicLogEndToEndTest', 'parallelGrokStringSubstituteTest']
	fail-fast: false

	runs-on: ubuntu-latest

	steps:
	- name: Set up JDK 11
	uses: actions/setup-java@v1
	with:
	java-version: 11
	- name: Checkout Data Prepper
	uses: actions/checkout@v2
	- name: Run basic grok end-to-end tests with Gradle
	run: ./gradlew -PendToEndJavaVersion=${{ matrix.java }} :e2e-test:log:${{ matrix.test }}

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