OZG-7573 OZG-7991 Make FileSender override methods that return this

ozgcloud-common-lib/src/main/java/de/ozgcloud/common/binaryfile/GrpcFileUploadUtils.java

@@ -32,6 +32,7 @@ import io.grpc.stub.CallStreamObserver;
 import io.grpc.stub.StreamObserver;
 import lombok.AccessLevel;
 import lombok.NoArgsConstructor;
+import lombok.NonNull;
 import lombok.extern.log4j.Log4j2;
 
 @Log4j2
@@ -74,6 +75,18 @@ public class GrpcFileUploadUtils {
 				Function<StreamObserver<S>, CallStreamObserver<Q>> reqObserverBuilder) {
 			super(chunkBuilder, inputStream, reqObserverBuilder);
 		}
+
+		@Override
+		public FileSender<Q, S> send() {
+			super.send();
+			return this;
+		}
+
+		@Override
+		public FileSender<Q, S> withMetaData(@NonNull Q metaData) {
+			super.withMetaData(metaData);
+			return this;
+		}
 	}
 
 }
\ No newline at end of file