[SPARK-52201] Revisit PMD annotations

### What changes were proposed in this pull request?

This PR aims to revisit `PMD` annotations.

### Why are the changes needed?

We can remove or reduce the scope.

**BEFORE**

```
$ git grep PMD | wc -l
       5
```

**AFTER**

```
$ git grep PMD | wc -l
       3
```

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Manual review.

### Was this patch authored or co-authored using generative AI tooling?

No.

Closes #210 from dongjoon-hyun/SPARK-52201.

Authored-by: Dongjoon Hyun <[email protected]>
Signed-off-by: Dongjoon Hyun <[email protected]>

Author: dongjoon-hyun

config/pmd/ruleset.xml

@@ -26,7 +26,6 @@
     <exclude name="ImplicitFunctionalInterface" />
     <exclude name="UnitTestAssertionsShouldIncludeMessage" />
     <exclude name="UnitTestContainsTooManyAsserts" />
-    <exclude name="UnitTestShouldIncludeAssert" />
     <exclude name="UnusedLocalVariable" />
     <exclude name="LooseCoupling" />
   </rule>

spark-operator/src/test/java/org/apache/spark/k8s/operator/metrics/sink/MockSink.java

@@ -28,7 +28,7 @@
 
 import org.apache.spark.metrics.sink.Sink;
 
-@SuppressWarnings("PMD")
+@SuppressWarnings("PMD.UnusedPrivateField")
 public class MockSink implements Sink {
   private static final Logger logger = LoggerFactory.getLogger(MockSink.class);
   private final Properties properties;

spark-operator/src/test/java/org/apache/spark/k8s/operator/metrics/source/KubernetesMetricsInterceptorTest.java

@@ -49,7 +49,6 @@
 
 @EnableKubernetesMockClient(crud = true)
 @TestMethodOrder(MethodOrderer.OrderAnnotation.class)
-@SuppressWarnings("PMD")
 @SuppressFBWarnings(
     value = {"UWF_UNWRITTEN_FIELD", "NP_UNWRITTEN_FIELD", "UUF_UNUSED_FIELD"},
     justification = "Unwritten fields are covered by Kubernetes mock client")

spark-operator/src/test/java/org/apache/spark/k8s/operator/probe/ProbeServiceTest.java

@@ -43,7 +43,7 @@
 
 import org.apache.spark.k8s.operator.metrics.healthcheck.SentinelManager;
 
-@SuppressWarnings("PMD.JUnitTestsShouldIncludeAssert")
+@SuppressWarnings("PMD.UnitTestShouldIncludeAssert")
 @EnableKubernetesMockClient
 class ProbeServiceTest {
   @Test

spark-operator/src/test/java/org/apache/spark/k8s/operator/probe/ReadinessProbeTest.java

@@ -37,7 +37,7 @@
 
 import org.apache.spark.k8s.operator.utils.ProbeUtil;
 
-@SuppressWarnings("PMD.JUnitTestsShouldIncludeAssert")
+@SuppressWarnings("PMD.UnitTestShouldIncludeAssert")
 class ReadinessProbeTest {
   KubernetesClient client;
   HttpExchange httpExchange;

spark-operator/src/test/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppInitStepTest.java

@@ -52,7 +52,6 @@
 import org.apache.spark.k8s.operator.utils.SparkAppStatusRecorder;
 
 @EnableKubernetesMockClient(crud = true)
-@SuppressWarnings("PMD")
 @SuppressFBWarnings(
     value = {"UWF_UNWRITTEN_FIELD", "NP_UNWRITTEN_FIELD", "UUF_UNUSED_FIELD"},
     justification = "Unwritten fields are covered by Kubernetes mock client")