[TEST] Clean RestRequestTests (#131359)

Clean `RestRequestTests`

Fix IntelliJ code clean suggestions inside `RestRequestTests`

Author: joshua-adams-1

server/src/test/java/org/elasticsearch/rest/RestRequestTests.java

@@ -22,6 +22,7 @@
 import org.elasticsearch.xcontent.XContentParser;
 import org.elasticsearch.xcontent.XContentParserConfiguration;
 import org.elasticsearch.xcontent.XContentType;
+import org.junit.Assert;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -170,7 +171,7 @@ public void testParamAsIntegerWithNonIntegerParameter() {
         assertThrows(IllegalArgumentException.class, () -> restRequest.paramAsInteger(parameterKey, defaultValue));
     }
 
-    public void testContentOrSourceParam() throws IOException {
+    public void testContentOrSourceParam() {
         Exception e = expectThrows(ElasticsearchParseException.class, () -> contentRestRequest("", emptyMap()).contentOrSourceParam());
         assertEquals("request body or source parameter is required", e.getMessage());
         assertEquals(new BytesArray("stuff"), contentRestRequest("stuff", emptyMap()).contentOrSourceParam().v2());
@@ -188,11 +189,11 @@ public void testContentOrSourceParam() throws IOException {
         assertThat(e.getMessage(), containsString("source and source_content_type parameters are required"));
     }
 
-    public void testHasContentOrSourceParam() throws IOException {
-        assertEquals(false, contentRestRequest("", emptyMap()).hasContentOrSourceParam());
-        assertEquals(true, contentRestRequest("stuff", emptyMap()).hasContentOrSourceParam());
-        assertEquals(true, contentRestRequest("stuff", singletonMap("source", "stuff2")).hasContentOrSourceParam());
-        assertEquals(true, contentRestRequest("", singletonMap("source", "stuff")).hasContentOrSourceParam());
+    public void testHasContentOrSourceParam() {
+        assertFalse(contentRestRequest("", emptyMap()).hasContentOrSourceParam());
+        assertTrue(contentRestRequest("stuff", emptyMap()).hasContentOrSourceParam());
+        assertTrue(contentRestRequest("stuff", singletonMap("source", "stuff2")).hasContentOrSourceParam());
+        assertTrue(contentRestRequest("", singletonMap("source", "stuff")).hasContentOrSourceParam());
     }
 
     public void testContentOrSourceParamParser() throws IOException {
@@ -210,7 +211,7 @@ public void testContentOrSourceParamParser() throws IOException {
     }
 
     public void testWithContentOrSourceParamParserOrNull() throws IOException {
-        contentRestRequest("", emptyMap()).withContentOrSourceParamParserOrNull(parser -> assertNull(parser));
+        contentRestRequest("", emptyMap()).withContentOrSourceParamParserOrNull(Assert::assertNull);
         contentRestRequest("{}", emptyMap()).withContentOrSourceParamParserOrNull(parser -> assertEquals(emptyMap(), parser.map()));
         contentRestRequest("{}", singletonMap("source", "stuff2")).withContentOrSourceParamParserOrNull(
             parser -> assertEquals(emptyMap(), parser.map())
@@ -307,7 +308,7 @@ public void testRequiredContent() {
     public void testIsServerlessRequest() {
         RestRequest request1 = contentRestRequest("content", new HashMap<>());
         request1.markAsServerlessRequest();
-        assertEquals(request1.param(SERVERLESS_REQUEST), "true");
+        assertEquals("true", request1.param(SERVERLESS_REQUEST));
         assertTrue(request1.isServerlessRequest());
         IllegalArgumentException exception = expectThrows(IllegalArgumentException.class, request1::markAsServerlessRequest);
         assertThat(exception.getMessage(), is("The parameter [" + SERVERLESS_REQUEST + "] is already defined."));
@@ -320,7 +321,7 @@ public void testIsServerlessRequest() {
     public void testIsOperatorRequest() {
         RestRequest request1 = contentRestRequest("content", new HashMap<>());
         request1.markAsOperatorRequest();
-        assertEquals(request1.param(OPERATOR_REQUEST), "true");
+        assertEquals("true", request1.param(OPERATOR_REQUEST));
         assertTrue(request1.isOperatorRequest());
         IllegalArgumentException exception = expectThrows(IllegalArgumentException.class, request1::markAsOperatorRequest);
         assertThat(exception.getMessage(), is("The parameter [" + OPERATOR_REQUEST + "] is already defined."));