sumdb/note: remove stray bytes.Buffer from Open

This has been there from the beginning (CL 156324) without ever being
used.

Change-Id: I0cfb06ef1622315f84eb8ade525781e779012540
GitHub-Last-Rev: eb0423bad7d0998195a1730200a39f0fa1c49555
GitHub-Pull-Request: golang/mod#1
Reviewed-on: https://go-review.googlesource.com/c/mod/+/194639
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
1 file changed