Fix 2 idempotence issues

tasks/elasticsearch-Debian-version-lock.yml

@@ -1,3 +1,5 @@
 ---
 - name: Debian - hold elasticsearch version
   command: apt-mark hold elasticsearch
+  register: hold_elasticsearch_result
+  changed_when: "hold_elasticsearch_result.stdout != 'elasticsearch was already set on hold.'"

tasks/java.yml

@@ -16,6 +16,7 @@
 
 - command: java -version 2>&1 | grep OpenJDK
   register: open_jdk
+  changed_when: false
 
 - name: refresh the java ca-certificates
   command: /var/lib/dpkg/info/ca-certificates-java.postinst configure