remove fail_ci_if_error: false to surface upload failures

Per review feedback on guacsec/trustify#2376 — keep CI failing on
Codecov upload errors so broken coverage is caught immediately.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ptomanRH

.github/workflows/test.yml

@@ -121,5 +121,4 @@ jobs:
           flags: unit-tests
           files: ./coverage/lcov.info
           slug: guacsec/trustify-da-javascript-client
-          fail_ci_if_error: false