morph-rc1.5: build and deploy config with jdk-11

.gitlab-ci.yml

 # Gitlab CI/CD script for the Morphemic Preprocessor project
 
 variables:
-  MAVEN_IMAGE_JDK_8: "maven:3.5.2-jdk-8"
-  MAVEN_IMAGE_JDK_11: "maven:3.8.1-jdk-11"
+  MAVEN_IMAGE_JDK: "maven:3.8.1-jdk-11"
   LOCAL_REPO: "127.0.0.1:5000"
 
   DOCKER_REPO: "gitlab.ow2.org:4567"
@@ -37,7 +36,7 @@ stages:
 
 build:scheduling-abstraction-layer:
   stage: build
-  image: MAVEN_IMAGE_JDK_8
+  image: MAVEN_IMAGE_JDK
   script:
     - $SCHEDULING_ABSTRACTION_LAYER_CLI clean install
   artifacts:
@@ -46,7 +45,7 @@ build:scheduling-abstraction-layer:
 
 build:amq-message-java-library:
   stage: build
-  image: MAVEN_IMAGE_JDK_8
+  image: MAVEN_IMAGE_JDK
   script:
     - $AMQ_MESSAGE_JAVA_LIBRARY_CLI clean install
   artifacts:
@@ -55,7 +54,7 @@ build:amq-message-java-library:
 
 build:slo-severity-calculator:
   stage: build
-  image: MAVEN_IMAGE_JDK_11
+  image: MAVEN_IMAGE_JDK
   script:
     - $SLO_SEVERITY_CALCULATOR_CLI clean install
   artifacts:
@@ -112,7 +111,7 @@ deploy:persistent-storage-activemq:
 
 deploy:scheduling-abstraction-layer:
   stage: deploy
-  image: MAVEN_IMAGE_JDK_8
+  image: MAVEN_IMAGE_JDK
   only:
     - master
     - morphemic-rc1.5
@@ -123,7 +122,7 @@ deploy:scheduling-abstraction-layer:
 
 deploy:amq-message-java-library:
   stage: deploy
-  image: MAVEN_IMAGE_JDK_8
+  image: MAVEN_IMAGE_JDK
   only:
     - master
     - morphemic-rc1.5
@@ -134,7 +133,7 @@ deploy:amq-message-java-library:
 
 deploy:slo-severity-calculator:
   stage: deploy
-  image: MAVEN_IMAGE_JDK_11
+  image: MAVEN_IMAGE_JDK
   only:
     - master
     - morphemic-rc1.5