Use correct <a> tag syntax in javadoc @see tag

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=137946021

java/google/registry/util/UrlFetchUtils.java

@@ -64,7 +64,7 @@ public final class UrlFetchUtils {
    *
    * <p>This is equivalent to running the command: {@code curl -F fieldName=@payload.txt URL}
    *
-   * @see "http://www.ietf.org/rfc/rfc2388.txt"
+   * @see <a href="http://www.ietf.org/rfc/rfc2388.txt"> RFC2388 - Returning Values from Forms</a>
    */
   public static <T> void setPayloadMultipart(
       HTTPRequest request, String name, String filename, MediaType contentType, T data) {