[v9_11] Fix triggering rules for the "tarball-create" job
Commit de35d321 (a backport of commit 4d5d3b75) did not account for the fact that the "tarball-create" GitLab CI job is not created for manually triggered pipelines. This prevents manual pipeline creation from succeeding as it causes the "gcc:tarball" job to have unsatisfied dependencies. Make sure the "tarball-create" job is created for manually triggered pipelines to allow such pipelines to be started again.
See !4853 (merged)