Remove the VENVOmitUseWheel field now that nothing uses it.
Remove the VENVOmitUseWheel field now that nothing uses it.

Change-Id: I9ff1cc6c83a09b4ebc034023320f5d5caffe5cf0
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/3534925
Auto-Submit: Brian Ryner <388ea68edb4d8f934960c128120aee09a8f854bf@google.com>
Reviewed-by: Chenlin Fan <ade7e59805b81f027d537665b2c12c1956198b97@chromium.org>
Commit-Queue: Chenlin Fan <ade7e59805b81f027d537665b2c12c1956198b97@chromium.org>

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go