Use JUnit Pioneer @DefaultLocale to avoid side effects

Author: garydgregory

src/test/java/org/apache/commons/lang3/StringUtilsTest.java

@@ -51,6 +51,7 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
+import org.junitpioneer.jupiter.DefaultLocale;
 import org.junitpioneer.jupiter.ReadsDefaultLocale;
 import org.junitpioneer.jupiter.WritesDefaultLocale;
 
@@ -3102,14 +3103,13 @@ public void testToRootLowerCase() {
         assertNotEquals("title", "TITLE".toLowerCase(TURKISH));
         assertEquals("title", "TITLE".toLowerCase(Locale.ROOT));
         assertEquals("title", StringUtils.toRootLowerCase("TITLE"));
-        // Make sure we are not using the default Locale:
-        final Locale defaultLocale = Locale.getDefault();
-        try {
-            Locale.setDefault(TURKISH);
-            assertEquals("title", StringUtils.toRootLowerCase("TITLE"));
-        } finally {
-            Locale.setDefault(defaultLocale);
-        }
+    }
+
+    @Test
+    @DefaultLocale("tr")
+    @ReadsDefaultLocale
+    public void testToRootLowerCaseTurkish() {
+        assertEquals("title", StringUtils.toRootLowerCase("TITLE"));
     }
 
     @Test