[#3664] Update Jenkins website build job to use Hugo 0.123.8

Also increased memory of JNLP container to 1GB because the original
512MB seems to have caused sporadic failures to execute the job.

jenkins/Hono-Website-Pipeline-Declarative.groovy

@@ -34,13 +34,13 @@ pipeline {
               value: "/home/jenkins"
             resources:
               limits:
-                memory: "512Mi"
+                memory: "1Gi"
                 cpu: "1"
               requests:
-                memory: "512Mi"
+                memory: "1Gi"
                 cpu: "1"
           - name: "hugo"
-            image: "cibuilds/hugo:0.102"
+            image: "cibuilds/hugo:0.123.8"
             command:
             - cat
             tty: true
@@ -114,7 +114,7 @@ pipeline {
             # removing them, so they don't get deployed.
             rm themes/hugo-universal-theme/static/img/*
             echo "building home page..."
-            hugo -v -d "${WEBSITE_REPO_DIR}"
+            hugo build -d "${WEBSITE_REPO_DIR}"
           '''
         }
       }
@@ -170,7 +170,7 @@ pipeline {
           sh '''#!/bin/bash
             echo "building documentation..."
             cd "${DOC_ASSEMBLY_DIR}"
-            hugo -v -d "${WEBSITE_REPO_DIR}/docs" --config config.toml,config_version.toml
+            hugo build -d "${WEBSITE_REPO_DIR}/docs" --config config.toml,config_version.toml
           '''
         }
       }