Parameterize the JDK distribution

Change-Id: Idcc0f9348ec257bc0382de68422af2b141cec413
diff --git a/jjb/defaults.yaml b/jjb/defaults.yaml
index 9ed426c..901d11b 100644
--- a/jjb/defaults.yaml
+++ b/jjb/defaults.yaml
@@ -173,3 +173,7 @@
     # Currently used with: github-release
     artifact-glob: ''
 
+    # JDK distribution to use
+    # Give the version of the JDK to use when building
+    # Parameter is used with `update-java-alternatives --set <jdk-distribution>`
+    jdk-distribution: 'java-11-amazon-corretto'