Make TestClassScanner and TestContextAotGenerator public

This commit makes TestClassScanner and TestContextAotGenerator public so
that the Spring Boot team can take over implementation of the
TestAotProcessor to integrate it into the AOT and native build plugins.

spring-test/src/main/java/org/springframework/test/context/aot/TestClassScanner.java

@@ -79,7 +79,7 @@ import static org.springframework.core.annotation.MergedAnnotations.SearchStrate
  * @author Sam Brannen
  * @since 6.0
  */
-class TestClassScanner {
+public class TestClassScanner {
 
 	// JUnit Jupiter
 	private static final String EXTEND_WITH_ANNOTATION_NAME = "org.junit.jupiter.api.extension.ExtendWith";
@@ -103,7 +103,7 @@ class TestClassScanner {
 	 * absolute path to the project's {@code build/classes/java/test} folder.
 	 * @param classpathRoots the classpath roots to scan
 	 */
-	TestClassScanner(Set<Path> classpathRoots) {
+	public TestClassScanner(Set<Path> classpathRoots) {
 		this.classpathRoots = assertPreconditions(classpathRoots);
 	}
 
@@ -111,7 +111,7 @@ class TestClassScanner {
 	/**
 	 * Scan the configured classpath roots for Spring integration test classes.
 	 */
-	Stream<Class<?>> scan() {
+	public Stream<Class<?>> scan() {
 		return scan(new String[0]);
 	}
 

spring-test/src/main/java/org/springframework/test/context/aot/TestContextAotGenerator.java

@@ -53,7 +53,7 @@ import org.springframework.util.MultiValueMap;
  * @since 6.0
  * @see ApplicationContextAotGenerator
  */
-class TestContextAotGenerator {
+public class TestContextAotGenerator {
 
 	private static final Log logger = LogFactory.getLog(TestContextAotGenerator.class);