FAST: fix Gitlab WIF attributes

[ludoo]

This removes unsupported attributes and adds supported ones to the Gitlab mapping used for Workload Identity Federation pools.

Tested with the following condition:

cicd_repositories = {
  bootstrap = {
    branch            = "main"
    identity_provider = "gitlab-ludomagno"
    name              = "ludomagno/fast-test"
    type              = "gitlab"
  }
}
federated_identity_providers = {
  gitlab-ludomagno = {
    attribute_condition = "attribute.namespace_path==\"ludomagno\""
    issuer              = "gitlab"
  }
}