Refactored sec scan function

vars/secops.groovy

@@ -1,6 +1,10 @@
 def secScan(script, image) {
+    def reportDir = "/var/jenkins_home/secscan_reports/${script.env.JOB_NAME}/"
+    def imageName = image.split("/").last().replaceAll("[:/]", "_")
+    def timestamp = new Date().format("yyyyMMdd_HHmmss")
+    def reportName = "secscan_report_${imageName}_${timestamp}.html"
     sh """
-        mkdir -p /var/jenkins_home/secscan_reports/${script.env.JOB_NAME}/
+        mkdir -p ${reportDir}
         docker run \
         -v ./trivy_cache:/root/.cache \
         -v /var/run/docker.sock:/var/run/docker.sock \
@@ -9,6 +13,6 @@ def secScan(script, image) {
         --template "@contrib/html.tpl" \
         -o /dev/stdout \
         image --exit-code 1 --severity HIGH,CRITICAL \
-        ${image} > /var/jenkins_home/secscan_reports/${script.env.JOB_NAME}/secscan_report_\$(date +"%Y%m%d_%H%M%S")_${image}.html
+        ${image} > ${reportDir}/${reportName}
     """
 }