Scan for vulnerabilities on build

Jenkinsfile

@@ -37,6 +37,14 @@ pipeline {
             }
         }
 
+        stage('Security scan') {
+            steps {
+                sh "docker run --name sectest registry.jakecharman.co.uk/jakecharman.co.uk:$BUILD_NUMNER"
+                sh "docker exec sectest pip3 install pip-audit"
+                sh "docker exec sectest pip-audit"
+            }
+        }
+
         stage('Push to registry') {
             when {
                 expression {