BATS upgrade tests fails on master branch because it tries to install 2.x versions to upgrade from instead of 5.x versions. And since #18554 we should only test upgrades from 5.0.0-alpha4 versions.
This commit changes the vagrant tests so that it tries to list all the previous releases from version N-1. If nothing is found, it will fetch the current version and will run the upgrade tests with it. It works nicely with the current master 6.0.0-alpha1-SNAPSHOT. Once 5.0.0 is released it should run the test with it.
This commit adds randomization for the packaging upgrade test. In
particular, we extract a list of the released version of Elasticsearch
from Maven Central and randomize the selection of the version to upgrade
from. The randomization is repeatable, and supports the tests.seed
property. Specific versions can be tested by setting the property
tests.packaging.upgrade.from.versions.
Relates #19033
Nik Everett
Ali Beyad
Tanguy Leroux
Igor Motov
Jason Tedor