crosperf: Increase timeout for a crosfleet call

Current timeout 2 min may not be sufficiant for `crosfleet dut
lease`.
Many tests fail with the lock error while lease succeeds.
Increase the timeout to 8 minutes.
Remove backslashes and fix other minor lints to make upload happy.

BUG=b:205325997
TEST=run crosperf locally on veyron

Change-Id: Ie3b74a0036cce3daeb58379fc5362797b0e5db03
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/3265564
Tested-by: Denis Nikitin <denik@chromium.org>
Commit-Queue: Denis Nikitin <denik@chromium.org>
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
1 file changed