OZG-6754 Remove unused method

src/test/java/de/ozgcloud/xta/client/factory/ZipFileTestFactory.java

@@ -5,13 +5,10 @@ import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.List;
-import java.util.function.UnaryOperator;
 import java.util.stream.Stream;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipOutputStream;
 
-import jakarta.annotation.Nullable;
-
 import org.apache.commons.codec.Resources;
 import org.apache.commons.io.IOUtils;
 
@@ -60,12 +57,6 @@ public class ZipFileTestFactory {
 				).toList());
 	}
 
-	public static byte[] replaceXmlString(byte[] data, @Nullable UnaryOperator<String> xmlStringReplacer) {
-		return xmlStringReplacer == null
-				? data
-				: xmlStringReplacer.apply(new String(data, StandardCharsets.UTF_8)).getBytes(StandardCharsets.UTF_8);
-	}
-
 	static Stream<String> listResourceFileNames(String resourceDirectoryPath) {
 		try (var inputStream = Resources.getInputStream(resourceDirectoryPath)) {
 			return Arrays.stream(IOUtils.toString(inputStream, StandardCharsets.UTF_8).split("\n"));