[bug-64879] SXSSFSheet dispose() fails to remove Temporary files for java.io.IOException: No space left on device

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1883171 13f79535-47bb-0310-9956-ffa450edef68

src/ooxml/java/org/apache/poi/xssf/streaming/SXSSFSheet.java

@@ -1916,6 +1916,7 @@ public class SXSSFSheet implements Sheet
         } finally {
             ret = _writer == null || _writer.dispose();
         }
+        return ret;
     }
 
     @Override