[CSV-211] fix CSVFormat.format trims last delimiter if the delimiter is a white space

Author: dota17

src/main/java/org/apache/commons/csv/CSVFormat.java

@@ -894,7 +894,9 @@ public String format(final Object... values) {
         final StringWriter out = new StringWriter();
         try (CSVPrinter csvPrinter = new CSVPrinter(out, this)) {
             csvPrinter.printRecord(values);
-            return out.toString().trim();
+            String res = out.toString();
+            int len = recordSeparator != null ? res.length() - recordSeparator.length() : res.length();
+            return res.substring(0, len);
         } catch (final IOException e) {
             // should not happen because a StringWriter does not do IO.
             throw new IllegalStateException(e);