ci: refs #6695 streamline Cypress E2E test execution in Jenkinsfile and improve error handling

Jenkinsfile

@@ -115,6 +115,7 @@ pipeline {
                                 docker run --network \${env.NETWORK}_e2e-network \\
                                 -e TZ=Europe/Madrid \\
                                 -e DOCKER=true \\
+                                -e CI=true \\
                                 -v \$(pwd):/app \\
                                 -w /app \\
                                 cypress/included:latest \\
@@ -169,8 +170,8 @@ pipeline {
 
 def cleanDockerE2E() {
     script {
-        sh "docker-compose -p ${env.NETWORK} -f docker-compose.e2e.yml down || true"
-        sh "docker rm ${containerId} || true"
+        sh(script: "docker-compose -p ${env.NETWORK} -f docker-compose.e2e.yml down", returnStatus: true)
+        sh(script: "docker rm ${containerId}", returnStatus: true)
     }
 }