Bug when reviewing the latest version when not viewing the diff from PR base: Shows "Marking files as viewed is only supported when viewing this PR's latest version." when we're viewing the latest version, just from a different base

(If applicable) To help us repro, please send the following if you haven't already: - PR links, screenshots, and/or debug output if applicable - Repro steps - Does this happen consistently? Just to you or others on your team also? - Is this a regression? Is the problem new? - If you're having an issue with the CLI, please send us debug logs using

gt feedback --with-debug-context <any message>