feat: add spark-pi example

apps/base/kubeflow/spark.yaml

@@ -25,3 +25,44 @@ spec:
         namespace: kubeflow
       interval: 24h
   values: []
+---
+apiVersion: "sparkoperator.k8s.io/v1beta2"
+kind: SparkApplication
+metadata:
+  name: spark-pi
+  namespace: kubeflow
+spec:
+  type: Scala
+  mode: cluster
+  image: "gcr.io/spark-operator/spark:v3.1.1"
+  imagePullPolicy: Always
+  mainClass: org.apache.spark.examples.SparkPi
+  mainApplicationFile: "local:///opt/spark/examples/jars/spark-examples_2.12-3.1.1.jar"
+  sparkVersion: "3.1.1"
+  restartPolicy:
+    type: Never
+  volumes:
+    - name: "test-volume"
+      hostPath:
+        path: "/tmp"
+        type: Directory
+  driver:
+    cores: 1
+    coreLimit: "1200m"
+    memory: "512m"
+    labels:
+      version: 3.1.1
+    # Ensure the service account matches what is set up by the spark-operator HelmRelease
+    serviceAccount: spark-operator-spark
+    volumeMounts:
+      - name: "test-volume"
+        mountPath: "/tmp"
+  executor:
+    cores: 1
+    instances: 1
+    memory: "512m"
+    labels:
+      version: 3.1.1
+    volumeMounts:
+      - name: "test-volume"
+        mountPath: "/tmp"