Fix misformatted GFM Table in BackendService

[TBBle]

See https://open-match.dev/site/docs/reference/api/#backendservice

[Laremere]

Unfortunately, this file is automatically generated so a fix here will be broken next time it is changed: https://github.com/googleforgames/open-match/blob/master/Makefile#L662

It looks like this is the tool which is used and needs to be fixed: https://github.com/pseudomuto/protoc-gen-doc/

[TBBle]

Drat. I'd seen direct commits to this file as part of doc updates in the file history, but there wasn't a mention in the few commits I looked at (or the file itself) of auto-generation.

We might want to remove the 'Edit this Page' link from the page, or all autogenerated pages if any others exist, since that is I got here in the first place.

If I find time later, I might come back and look into the tool, but I don't even have an Open Match source checkout, so this is pretty low on my priority list.

I don't see an issue in their tracker for the newlines in the type description, but I suspect pseudomuto/protoc-gen-doc#274 is related.

I do see pseudomuto/protoc-gen-doc#282 which might be related to why the Scalar Value Types table fails to render as a table on the site, but looks fine in the GitHub Markdown preview. It might be that the HTML renderer for the site isn't using expecting whatever flavour of Markdown protoc-gen-doc outputs.

Thanks anyway.

[Laremere]

Thanks for the investigation, opened an issue so this info isn't lost: #188