Sonar analysis failing due to obsolete Node version
This came up in a recent pull request build:

> [ERROR] Failed to execute goal org.sonarsource.scanner.maven:sonar-maven-plugin:3.8.0.2131:sonar (default-cli) on project java-design-patterns:
> [ERROR]
> [ERROR] The version of node.js (12) you have used to run this analysis is deprecated and we stopped accepting it.
> [ERROR] Please update to at least node.js 14. You can find more information here: https://docs.sonarcloud.io/appendices/scanner-environment/

Acceptance criteria

- Node version used in the CI build has been upgraded to fix the Sonar analysis

.circleci/config.yml
.circleci/config.yml
diff --git a/.circleci/config.yml b/.circleci/config.yml
index 3e35aee712dd..dad7997a8699 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -26,12 +26,14 @@ version: 2
 jobs:
   sonar-pr:
     docker:
-      - image: circleci/openjdk:11-node
+      - image: cimg/openjdk:11.0-node
     steps:
     - checkout
     - restore_cache:
         key: jdp-sonar-pr-{{ checksum "pom.xml" }}
     - run: |
+        sudo apt-get update
+        sudo apt-get install -y openjdk-11-jdk xvfb
         if [ -n "${CIRCLE_PR_NUMBER}" ]; then
           MAVEN_OPTS="-Xmx3000m" xvfb-run ./mvnw -B clean verify org.sonarsource.scanner.maven:sonar-maven-plugin:sonar \
              -Dsonar.pullrequest.key=${CIRCLE_PR_NUMBER} \
