testing running from inside containers

.jenkins/jenkinsfile

@@ -3,6 +3,15 @@ pipeline {
 
     stages {
         stage('Build C#') {
+            agent {
+                docker {
+                    image 'mcr.microsoft.com/dotnet/sdk:7.0'
+                    // Run the container on the node specified at the
+                    // top-level of the Pipeline, in the same workspace,
+                    // rather than on a new node entirely:
+                    reuseNode true
+                }
+            }
             steps {
                 dotnetRestore project: "Selector.Core.sln"
                 dotnetBuild project: "Selector.Core.sln"
@@ -10,6 +19,15 @@ pipeline {
         }
 
         stage('Build Javascript') {
+            agent {
+                docker {
+                    image 'node:16'
+                    // Run the container on the node specified at the
+                    // top-level of the Pipeline, in the same workspace,
+                    // rather than on a new node entirely:
+                    reuseNode true
+                }
+            }
             steps {
                 dir ('Selector.Web') {
                     sh "npm ci"
@@ -18,6 +36,15 @@ pipeline {
             }
         }
         stage('Test') {
+            agent {
+                docker {
+                    image 'mcr.microsoft.com/dotnet/sdk:7.0'
+                    // Run the container on the node specified at the
+                    // top-level of the Pipeline, in the same workspace,
+                    // rather than on a new node entirely:
+                    reuseNode true
+                }
+            }
             steps {
                 dotnetTest project: "Selector.Core.sln"
             }