message: [web] fix option require error in otbr-web
  The typo is fixed and now -v option could correctly print version information.
diff: @@ -78,7 +78,7 @@ int main(int argc, char **argv)
  int opt;
  uint16_t port = OT_HTTP_PORT;
  - while ((opt = getopt(argc, argv, "d:I:p:v:a:")) != -1)
  + while ((opt = getopt(argc, argv, "d:I:p:va:")) != -1)
  {
  switch (opt)
  {
  