There's a lot of demand for the Gitlab badges (#541) and the PR has been lingering, so I thought I'd start off one of the simple ones as a new-style service. This one is SVG-based, so it shouldn't require the API-token logic which could use some more testing and will require us to create an app and configure it on our server.
We don't have any validation in place for `queryParams`. Probably this should be added to BaseService, though for the time being I extracted a helper function.
Thanks to @LVMBDV for getting this work started in #1838!
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