Fix label for Fulfillment Platform team

This MR updates the label for the groupfulfillment platform team from group::fulfillment%20platform to group::fulfillment platform. The inclusion of %20 in the label causes the link to the issue lists (e.g. "All closed issues") incorrectly apply the label.

I tested this by running this task locally. The following are links generated before the label change:

[All closed issues]: https://gitlab.com/dashboard/issues?scope=all&state=closed&label_name[]=group%3A%3Afulfillment%2520platform&milestone_title=15.6
[Issues that slipped]: https://gitlab.com/dashboard/issues?scope=all&label_name[]=group%3A%3Afulfillment%2520platform&label_name[]=missed%3A15.6

And these are the links after the label change:

[All closed issues]: https://gitlab.com/dashboard/issues?scope=all&state=closed&label_name[]=group%3A%3Afulfillment%20platform&milestone_title=15.6
[Issues that slipped]: https://gitlab.com/dashboard/issues?scope=all&label_name[]=group%3A%3Afulfillment%20platform&label_name[]=missed%3A15.6