[packaging-ci] use reverify instead of rebuild

[Igor Yozhikov]

At present moment developers and package maintainers have not ability to relaunch verification for fallen gate jobs due absence of special commit message tag like reverify.
Only one commit message tag is usable = rebuild wich triggers pkg-build-spec and pkg-gate. It takes 2 more time because of run all jobs from pkg-build-spec and only after that relaunch pkg-gate.

For example: CR https://review.fuel-infra.org/#/c/13578/
spent 5 hours in pkg-build-spec after last rebuild command and only after that was moved into pkg-gate

Patch Set 13: Package repository: - package.repository http://perestroika-repo-tst.infra.mirantis.net/review/CR-13578/mos-repos//centos/mos8.0-centos7-fuel/os/x86_64 : LINK 12:31 PM
Patch Set 13: Verified+1 Build succeeded (pkg-build pipeline). - 8.0-pkg-pipeline-centos https://packaging- : SUCCESS 5:31 PM

5:31PM - 12:31 PM = 5hrs

Conclusion: we need REVERIFY instead of REBUILD for failed gate jobs

[Igor Yozhikov (iyozhikov)]

High because of double time required, time is expensive + lab resource usage

[Alexander Evseev (aevseev)]

Keyword "reverify" is used by infra CI

[Aleksandra Fedorova (bookwar)]

Gate failure for one patch affects all patches in the gate. Thus it is important to have patch properly tested before it enters the gate. And there shouldn't be any possibility to restart the gate without restarting the check pipeline first.

We will implement this feature only to be usable by CI engineers, so that we would be able to retrigger the gate only when it is confirmed with CI team that there is a gate issue.

[Aleksandra Fedorova (bookwar)]

https://review.fuel-infra.org/#/c/13784/

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/13784
Submitter: Alexander Evseev <email address hidden>
Branch: master

Commit: 13d718df72cd4ecad5e4f8e91ade8e18b80cea6b
Author: Alexander Evseev <email address hidden>
Date: Tue Nov 24 12:36:53 2015

Allow gate triggering by comment if CR has Verified+2

Closes-Bug: #1518367
Change-Id: I79d7d90159dadae52d9068bd94dcb30d63d6ea25