Remove useless @RegisterExtension on CliTester

Closes gh-17266

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/ClassLoaderIntegrationTests.java

@@ -18,7 +18,6 @@ package org.springframework.boot.cli;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.jupiter.api.extension.RegisterExtension;
 
 import org.springframework.boot.test.system.CapturedOutput;
 import org.springframework.boot.test.system.OutputCaptureExtension;
@@ -33,8 +32,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 @ExtendWith(OutputCaptureExtension.class)
 class ClassLoaderIntegrationTests {
 
-	@RegisterExtension
+	private final CliTester cli;
-	private CliTester cli;
 
 	ClassLoaderIntegrationTests(CapturedOutput capturedOutput) {
 		this.cli = new CliTester("src/test/resources/", capturedOutput);

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/DirectorySourcesIntegrationTests.java

@@ -18,7 +18,6 @@ package org.springframework.boot.cli;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.jupiter.api.extension.RegisterExtension;
 
 import org.springframework.boot.test.system.CapturedOutput;
 import org.springframework.boot.test.system.OutputCaptureExtension;
@@ -33,8 +32,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 @ExtendWith(OutputCaptureExtension.class)
 class DirectorySourcesIntegrationTests {
 
-	@RegisterExtension
+	private final CliTester cli;
-	private CliTester cli;
 
 	DirectorySourcesIntegrationTests(CapturedOutput capturedOutput) {
 		this.cli = new CliTester("src/test/resources/dir-sample/", capturedOutput);

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/GrabCommandIntegrationTests.java

@@ -22,7 +22,6 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.jupiter.api.extension.RegisterExtension;
 
 import org.springframework.boot.cli.command.grab.GrabCommand;
 import org.springframework.boot.test.system.CapturedOutput;
@@ -41,8 +40,7 @@ import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 @ExtendWith(OutputCaptureExtension.class)
 class GrabCommandIntegrationTests {
 
-	@RegisterExtension
+	private final CliTester cli;
-	private CliTester cli;
 
 	GrabCommandIntegrationTests(CapturedOutput capturedOutput) {
 		this.cli = new CliTester("src/test/resources/grab-samples/", capturedOutput);

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/ReproIntegrationTests.java

@@ -20,7 +20,6 @@ import java.util.concurrent.ExecutionException;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.jupiter.api.extension.RegisterExtension;
 
 import org.springframework.boot.test.system.CapturedOutput;
 import org.springframework.boot.test.system.OutputCaptureExtension;
@@ -38,8 +37,7 @@ import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 @ExtendWith(OutputCaptureExtension.class)
 class ReproIntegrationTests {
 
-	@RegisterExtension
+	private final CliTester cli;
-	private CliTester cli;
 
 	ReproIntegrationTests(CapturedOutput capturedOutput) {
 		this.cli = new CliTester("src/test/resources/repro-samples/", capturedOutput);

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/RunCommandIntegrationTests.java

@@ -22,7 +22,6 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.jupiter.api.extension.RegisterExtension;
 
 import org.springframework.boot.cli.command.run.RunCommand;
 import org.springframework.boot.test.system.CapturedOutput;
@@ -38,8 +37,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 @ExtendWith(OutputCaptureExtension.class)
 class RunCommandIntegrationTests {
 
-	@RegisterExtension
+	private final CliTester cli;
-	private CliTester cli;
 
 	RunCommandIntegrationTests(CapturedOutput capturedOutput) {
 		this.cli = new CliTester("src/it/resources/run-command/", capturedOutput);

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/SampleIntegrationTests.java

@@ -22,7 +22,6 @@ import java.net.URI;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.junit.jupiter.api.extension.RegisterExtension;
 
 import org.springframework.boot.test.system.CapturedOutput;
 import org.springframework.boot.test.system.OutputCaptureExtension;
@@ -40,8 +39,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 @ExtendWith(OutputCaptureExtension.class)
 class SampleIntegrationTests {
 
-	@RegisterExtension
+	private final CliTester cli;
-	private CliTester cli;
 
 	SampleIntegrationTests(CapturedOutput capturedOutput) {
 		this.cli = new CliTester("samples/", capturedOutput);