Remove disable web checks from PRESUBMIT.
Remove disable web checks from PRESUBMIT.

I believe we should still run webchecks in CQ,
but it shouldn't be done inside PRESUBMIT.py.

R=vadimsh

Bug: 794670
Change-Id: Iaca93b06734e7e6bc4f197425f1ed123fa33c92f
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/3015836
Auto-Submit: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>
Commit-Queue: Vadim Shtayura <9f116ddb1b24f6fc1916a676eb17161b6c07dfc1@chromium.org>
Reviewed-by: Vadim Shtayura <9f116ddb1b24f6fc1916a676eb17161b6c07dfc1@chromium.org>

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