Add Java 11 home which is necessary for BWC builds of older branches

.ci/jobs.t/elastic+elasticsearch+pull-request+part-1-windows.yml

@@ -33,6 +33,7 @@
           properties-content: |
             JAVA_HOME=$USERPROFILE\\.java\\$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$USERPROFILE\\.java\\$ES_RUNTIME_JAVA
+            JAVA11_HOME=$USERPROFILE\\.java\\java11
             JAVA16_HOME=$USERPROFILE\\.java\\openjdk16
             GRADLE_TASK=checkPart1
       - batch: |

.ci/jobs.t/elastic+elasticsearch+pull-request+part-2-windows.yml

@@ -33,6 +33,7 @@
           properties-content: |
             JAVA_HOME=$USERPROFILE\\.java\\$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$USERPROFILE\\.java\\$ES_RUNTIME_JAVA
+            JAVA11_HOME=$USERPROFILE\\.java\\java11
             JAVA16_HOME=$USERPROFILE\\.java\\openjdk16
             GRADLE_TASK=checkPart2
       - batch: |

.ci/jobs.t/elastic+elasticsearch+pull-request+part-3-windows.yml

@@ -34,6 +34,7 @@
           properties-content: |
             JAVA_HOME=$USERPROFILE\\.java\\$ES_BUILD_JAVA
             RUNTIME_JAVA_HOME=$USERPROFILE\\.java\\$ES_RUNTIME_JAVA
+            JAVA11_HOME=$USERPROFILE\\.java\\java11
             JAVA16_HOME=$USERPROFILE\\.java\\openjdk16
             GRADLE_TASK=checkPart3
       - batch: |