LTC Resubmit auto-completition behaviour is strange

[pb00067]

When I resubmitting a passed STC test for LTC then following happens:

1. If I manually edit the test description putting LTC as prefix,
   then fishtest prepends another 'LTC:' to the description which looks weird:
   LTC: LTC for https://tests.stockfishchess....
   See https://tests.stockfishchess.org/tests/view/64d33e3d5b17f7c21c0e07a2

2. Next time I think I don't need to add the 'LTC' remark manually in the description, fishtest will do it.
   I resubmit LTC without editing the description.
   Now fishtest does also not add the LTC remark.
   See https://tests.stockfishchess.org/tests/view/64db0ce05b17f7c21c0ebdb5

I think this is a bug, or at least it can be done smarter.