stream-clone-tests: stop filtering non existent warning
This filtering was introduced in 74c004a515bc, however there is already no
warning in that changeset. So I guess the warnings existed when we the patch
was created but the problem was solved in another changeset that 74c004a515bc,
rebased on.
# So GitLab doesn't think we're using tons of Perl
*.t -linguist-detectable