fix: handle panic when waiting for default branch protection

Giannis Kepasrequested to merge
gitlab-community/gitlab-org/terraform-provider-gitlab:6816-fix-project-panic into main

What does this MR do and why?

Skips the default branch protection wait when creating a gitlab_project and the project has no default branch.

Related to #6816 (closed)

Edited by Heidi Berry

Merge request reports