gh-127847: Fix position in the special-cased zipfile seek (#127856)

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Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Peter Bierma <zintensitydev@gmail.com>
Co-authored-by: Jason R. Coombs <jaraco@jaraco.com>