Renaming Endpoint "Get All Mod Activity By Game"

[Melodatron]

Request to rename endpoint from "Get All Mod Activity By Game" to "Get All Mod Activity". (https://docs.mod.io/#get-all-mod-activity-by-game)
Reasoning: Matches rest of documentation such as "Get All Mods" (which are implicitly "By Game") (https://docs.mod.io/#get-all-mods)

[Patskimoto]

Fixed in next deploy.