New node creation for jenkins-jobs

[Aliaksandr Buhayeu]

We need a way to configure and run new jenkins-job on its own node with a new script dependencies and access to specific credentials (Slack token).

The `yaml` file with Slack credentials should be present for configuration:

slack_api_token: zfsdf-sdfsdf-sdfsd-fsdf # token for Slack authentication
slack_channel_name: #test # channel name, ex. #devops, where notifications would come in.

So we need a new node for jobs with credentials mentioned supplied.

Script expects credentials settings available under the path: `/etc/gerrit-notifier/settings.yaml`

Reason: the script for Gerrit events notifications (https://review.fuel-infra.org/#/c/19335/) that would be ran by a jenkins-job under the `servers/infra-ci/builders` section requires its own node where Slack credentials and basic config would be present.

[Andrey Nikitin (heos)]

Guys, what do you want from Fuel DevOps team?

[Andrey Nikitin (heos)]

Ticket to IT-team to create new VM: https://mirantis.jira.com/browse/IT-27807.

[Andrey Nikitin (heos)]

infra-ci-slave02-bud.fuel-infra.org was deployed with 'infraci_slave_custom' role. Please attach this server to Infra CI.