Merge branch '19-maven-source-directory-variable-is-not-set' into 'dev'

Resolve "Maven: source directory variable is not set"

Closes #19

See merge request !64

templates/Maven.yaml

@@ -192,6 +192,7 @@
   image: ${MAVEN_IMAGE}
   extends: .on-branch
   variables:
+    SRC_DIR: '.'
     MAVEN_IMAGE: hub.eole.education/proxyhub/library/maven:3.8.6-openjdk-8-slim
     MAVEN_OPTS: "-Dhttps.protocols=TLSv1.2 -Dmaven.repo.local=$CI_PROJECT_DIR/.m2/repository -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN -Dorg.slf4j.simpleLogger.showDateTime=true -Djava.awt.headless=true"
     MAVEN_CLI_OPTS: "--batch-mode --errors --fail-at-end --show-version -DinstallAtEnd=true -DdeployAtEnd=true"