Use sourceSet for java under 17

Author: ngocnhan-tran1996

Diff for: micrometer-osgi-test/build.gradle

@@ -26,9 +26,11 @@ dependencies {
 def testingBundle = tasks.register('testingBundle', Bundle) {
     archiveClassifier = 'tests'
     from sourceSets.test.output
+    if (javaLanguageVersion.asInt() < 17) {
+        sourceSet = sourceSets.tests
+    }
     bundle {
-        sourceSet = sourceSets.test
-        bnd = """\
+        bnd """\
             Bundle-SymbolicName: \${task.archiveBaseName}-\${task.archiveClassifier}
             Test-Cases: \${classes;HIERARCHY_INDIRECTLY_ANNOTATED;org.junit.platform.commons.annotation.Testable;CONCRETE}
             """.stripIndent()