GitLab CI: use low priority Gradle processes.

Author: greenrobot-team

.gitlab-ci.yml

@@ -16,7 +16,8 @@ variables:
   # Docker volume containing GRADLE_USER_HOME. If the container is stopped after a job
   # Gradle daemons may get killed, preventing proper clean-up of lock files in GRADLE_USER_HOME.
   # Configure file.encoding to always use UTF-8 when running Gradle.
-  GRADLE_OPTS: "-Dorg.gradle.daemon=false -Dfile.encoding=UTF-8"
+  # Use low priority processes to avoid Gradle builds consuming all build machine resources.
+  GRADLE_OPTS: "-Dorg.gradle.daemon=false -Dfile.encoding=UTF-8 -Dorg.gradle.priority=low"
   GITLAB_REPO_ARGS: "-PgitlabUrl=$CI_SERVER_URL -PgitlabTokenName=Job-Token -PgitlabPrivateToken=$CI_JOB_TOKEN"
   CENTRAL_REPO_ARGS: "-PsonatypeUsername=$SONATYPE_USER -PsonatypePassword=$SONATYPE_PWD"
   # CI_COMMIT_REF_SLUG is the branch or tag name, but web-safe (only 0-9, a-z)