Default moderation queue filtering to spam

[akatsoulas]

No description provided.

[escattone]

With this change, the /{locale}/flagged page doesn't work when selecting All reasons for the reason filter. In that case, the JS does a fetch with no reason added to the URL (since the value for the All reasons case is the empty string) and since the view function defaults to a reason of "spam" in that case, you only see the spam moderation items instead of all moderation items.

I'm thinking we'll either have to make the "spam" reason have a value of the empty string as well as give the All reasons selection a value of "all" or something like that, or else maybe we have to give the All reasons selection a value of "all" and keep the value of "spam" as well?

[escattone]

Something is still off. When I load the page initially, it shows spam only, but when I then change the reason filter to "All reasons", nothing changes. The reason remains "spam".

[escattone]

r+wc

I don't think the isInitialLoad-related code is needed. When I remove it, this PR works great for me.