Add Java 8 home environment variable

Author: mark-vieira

.ci/jobs.t/elastic+elasticsearch+multijob+platform-support-darwin.yml

@@ -10,6 +10,7 @@
           properties-content: |
             JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
+            JAVA8_HOME=$HOME/.java/java8
       - shell: |
           #!/usr/local/bin/runbld --redirect-stderr
           $WORKSPACE/.ci/scripts/run-gradle.sh -Dbwc.checkout.align=true check

.ci/jobs.t/elastic+elasticsearch+multijob+platform-support-unix.yml

@@ -36,6 +36,7 @@
           properties-content: |
             JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
+            JAVA8_HOME=$HOME/.java/java8
       - shell: |
           #!/usr/local/bin/runbld --redirect-stderr
           $WORKSPACE/.ci/scripts/run-gradle.sh -Dbwc.checkout.align=true check

.ci/jobs.t/elastic+elasticsearch+multijob+platform-support-windows.yml

@@ -33,6 +33,7 @@
           properties-content: |
             JAVA_HOME=$USERPROFILE\\.java\\$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$USERPROFILE\\.java\\$ES_RUNTIME_JAVA
+            JAVA8_HOME=$USERPROFILE\\.java\\java8
       - batch: |
           del /f /s /q %USERPROFILE%\.gradle\init.d\*.*
           mkdir %USERPROFILE%\.gradle\init.d

.ci/jobs.t/elastic+elasticsearch+periodic+ear.yml

@@ -11,6 +11,7 @@
           properties-content: |
             JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
+            JAVA8_HOME=$HOME/.java/java8
       - shell: |
           #!/bin/bash
           # Configure a dm-crypt volume backed by a file

.ci/jobs.t/elastic+elasticsearch+periodic+release-tests.yml

@@ -11,6 +11,7 @@
           properties-content: |
             JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
+            JAVA8_HOME=$HOME/.java/java8
       - shell: |
           #!/usr/local/bin/runbld --redirect-stderr
           $WORKSPACE/.ci/scripts/run-gradle.sh -Dbwc.checkout.align=true -Dbuild.snapshot=false \

.ci/templates.t/matrix-gradle-unix.yml

@@ -25,6 +25,7 @@
           properties-content: |
             JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
+            JAVA8_HOME=$HOME/.java/java8
             JAVA11_HOME=$HOME/.java/java11
             JAVA15_HOME=$HOME/.java/openjdk15
       - shell: |

.ci/templates.t/pull-request-gradle-unix.yml

@@ -25,6 +25,7 @@
           properties-content: |
             JAVA_HOME=$HOME/.java/$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$HOME/.java/$ES_RUNTIME_JAVA
+            JAVA8_HOME=$HOME/.java/java8
             JAVA11_HOME=$HOME/.java/java11
             JAVA15_HOME=$HOME/.java/openjdk15
       - shell: |