fix(objectstore): Do not apply default timeout to streams

[jjbayer]

With #5851 I violated what the comment on the config says:

    /// NOTE: This timeout applies to attachments that are already in-memory. Streaming uploads
    /// might take longer and are restricted independently by [`Upload::timeout`].

This PR fixes the regression and adds a test for it.

[cursor]

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[Dav1dde]

Duration::MAX is pretty long, is the alternative of just increasing the timeout for everything not an option?

[jjbayer]

Duration::MAX is pretty long, is the alternative of just increasing the timeout for everything not an option?

Makes sense, will follow-up.