Forge Github Org: Use login instead of name (#2104)

For "woodpecker-ci" the `name` is "Woodpecker CI"
 and the `login` is "woodpecker-ci"

Fixes #2092

This was causing the organization lookup to fail, because it looks up
using the `login`, when it did not find the organization, it would try
to create it. The creation would fail, because it uses the `name`, and
an organization with that `name` already exists.
Resulting in:

```
pq: duplicate key value violates unique constraint "UQE_orgs_name"
```

server/forge/gitlab/gitlab.go

@@ -717,7 +717,7 @@ func (g *GitLab) Org(ctx context.Context, u *model.User, owner string) (*model.O
 	}
 
 	return &model.Org{
-		Name:    groups[0].Name,
+		Name:    groups[0].FullPath,
 		Private: groups[0].Visibility != gitlab.PublicVisibility,
 	}, nil
 }