cmd/gerritbot: remove redundant type conversion
cmd/gerritbot: remove redundant type conversion

Change-Id: I14bc99997d72801a933a1554ea7ab6b0db3aa3ea
GitHub-Last-Rev: 3c12de9cfe525853515380ac816e54172d317d19
GitHub-Pull-Request: golang/build#45
Reviewed-on: https://go-review.googlesource.com/c/build/+/428981
TryBot-Result: Gopher Robot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Run-TryBot: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@golang.org>
Reviewed-by: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@golang.org>
Auto-Submit: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@golang.org>
Reviewed-by: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@google.com>
Reviewed-by: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>

golang/build,golang/build,golang/build,golang/build