title: Branches and Pull Requests are not visible in SonarQube dashboard?
body: <p>I am using SonarQube's Developer edition (8.4) with GitHub (community edition - not enterprise) to analyze Maven based java projects. I took this <a href="https://github.com/SonarSource/sonar-scanning-examples/tree/master/sonarqube-scanner-maven/maven-basic" rel="nofollow noreferrer">sample project</a> and followed all the steps mentioned in <a href="https://docs.sonarqube.org/latest/analysis/github-integration/" rel="nofollow noreferrer">this guide</a> to set up.</p>
  <p>I have a sample build.yaml file copied from the same tutorial, for a Maven project that looks like below:</p>
  <pre class="lang-yaml prettyprint-override"><code>name: Build
  on:
    push:
      branches:
        - master
        - develop
    pull_request:
      types: [opened, synchronize, reopened]
  jobs:
    build:
      name: Build
      runs-on: ubuntu-latest
      steps:
        - uses: actions/checkout@v2
          with:
            fetch-depth: 0  # Shallow clones should be disabled for a better relevancy of analysis
        - name: Set up JDK 11
          uses: actions/setup-java@v1
          with:
            java-version: 11
        - name: Cache SonarQube packages
          uses: actions/cache@v1
          with:
            path: ~/.sonar/cache
            key: ${{ runner.os }}-sonar
            restore-keys: ${{ runner.os }}-sonar
        - name: Cache Maven packages
          uses: actions/cache@v1
          with:
            path: ~/.m2
            key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
            restore-keys: ${{ runner.os }}-m2
        - name: Build and analyze
          env:
            GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}  # Needed to get PR information, if any
            SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
            SONAR_HOST_URL: ${{ secrets.SONAR_HOST_URL }}
          run: mvn -B verify org.sonarsource.scanner.maven:sonar-maven-plugin:sonar
  </code></pre>
  <p>Whenever a new code is pushed an analysis is done. I can see PR decorations and checks running for PRs as well in github's dashboard.</p>
  <p>However, I am not seeing any other branches except <code>master</code> or any Pull Requests in SonarQube's dashboard under <em><strong>Branches &amp; Pull Requests</strong></em>. Below are the screenshots for reference:</p>
  <p><em><strong>Branches (only master branch is visible. I have feature and develop branches too)</strong></em>
  <a href="https://i.stack.imgur.com/bAgRG.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bAgRG.png" alt="Branches tab Screenshot" /></a></p>
  <p><em><strong>Pull Requests</strong></em>
  <a href="https://i.stack.imgur.com/RJQMz.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/RJQMz.png" alt="PR Tab screenshot" /></a></p>
  <p>As per SonarQube's docs, I should be able to see multiple branches and PRs in the dashboard.</p>
  <p>Am I missing something?</p>