Replace all contexts in tests with go1.24 t.Context()
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Co-authored-by: Giteabot <teabot@gitea.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
We had an issue where a repo was using LFS to store a file, but the user
did not push the file. When trying to view the file, Gitea returned a
500 HTTP status code referencing `ErrLFSObjectNotExist`. It appears the
intent was the render this file as plain text, but the conditional was
flipped. I've also added a test to verify that the file is rendered as
plain text.
