Recipe - Refactor similar jobs with a matrix

Given the following workflow definition https://raw.githubusercontent.com/asyncer-io/r2dbc-mysql/f4ca1652219074c337d7db12d2572686da2c3a64/.github/workflows/unit-tests.yml

name: Unit tests

on: [ pull_request ]

jobs:
  build_java_8:
    runs-on: ubuntu-20.04
    steps:
      - uses: actions/checkout@v3
      - name: Set up Temurin 8
        uses: actions/setup-java@v3
        with:
          distribution: temurin
          java-version: 8
          cache: maven
      - name: Unit test with Maven
        run: ./mvnw -B test -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN
  build_java_11:
    runs-on: ubuntu-20.04
    steps:
      - uses: actions/checkout@v3
      - name: Set up Temurin 11
        uses: actions/setup-java@v3
        with:
          distribution: temurin
          java-version: 11
          cache: maven
      - name: Unit test with Maven
        run: ./mvnw -B test -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN
  build_java_17:
    runs-on: ubuntu-20.04
    steps:
      - uses: actions/checkout@v3
      - name: Set up Temurin 17
        uses: actions/setup-java@v3
        with:
          distribution: temurin
          java-version: 17
          cache: maven
      - name: Unit test with Maven
        run: ./mvnw -B test -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN

One could rewrite this workflow using a matrix configuration like so

name: Unit tests

on: [ pull_request ]

jobs:
  build:
    name: "Build ${{ matrix.java }}"
    strategy:
      fail-fast: false
      matrix:
        java: [8, 11, 17]
    runs-on: ubuntu-20.04
    steps:
      - uses: actions/checkout@v3
      - name: "Set up Temurin ${{ matrix.java }}"
        uses: actions/setup-java@v3
        with:
          distribution: temurin
          java-version: ${{ matrix.java }}
          cache: maven
      - name: Unit test with Maven
        run: ./mvnw -B test -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN

Start with the referenced .github/workflows/unit-tests.yml and compare its three Java-version jobs with the matrix example in the issue. Implement the recipe so the workflow runs Java 8, 11, and 17 through one matrix job, then verify that the generated workflow retains the checkout, Maven cache, and unit-test steps.