gitlab-ci: use maven artefacts cache only for build stages

.gitlab-ci.yml

@@ -8,19 +8,19 @@ variables:
   MAVEN_CLI_OPTS: "--batch-mode --errors --no-transfer-progress --fail-at-end --show-version -DinstallAtEnd=true -DdeployAtEnd=true  -Dmaven.repo.local=.m2/repository"
   REPO_NAME: dcache-cta
 
-# Cache downloaded dependencies and plugins between builds.
-# To keep cache across branches add 'key: "$CI_JOB_NAME"'
-cache:
-  key:
-    files:
-      - pom.xml
-    prefix: "$CI_JOB_NAME"
-  paths:
-    - ./.m2/repository
 
 build:
   stage: build
   image: maven:3.6.3-openjdk-11
+  # Cache downloaded dependencies and plugins between builds.
+  # To keep cache across branches add 'key: "$CI_JOB_NAME"'
+  cache:
+    key:
+      files:
+        - pom.xml
+      prefix: "$CI_JOB_NAME"
+    paths:
+      - ./.m2/repository
   script:
     - mvn $MAVEN_CLI_OPTS clean package
   artifacts:
@@ -36,6 +36,15 @@ build:
 build_java_next:
   stage: build
   image: maven:3.8.4-openjdk-17
+  # Cache downloaded dependencies and plugins between builds.
+  # To keep cache across branches add 'key: "$CI_JOB_NAME"'
+  cache:
+    key:
+      files:
+        - pom.xml
+      prefix: "$CI_JOB_NAME"
+    paths:
+      - ./.m2/repository
   script:
     - mvn $MAVEN_CLI_OPTS clean package
   artifacts: