Add a check in CI to ensure that minor version of a package is increased if kibana version is modified

[jsoriano]

We have a process to support multiple versions of the stack (docs), but it requires to be able to backport changes to an older minor. For this, this older minor needs to exist.

We could guarantee that this minor exist if CI forces to increase the minor version of a package every time the kibana version constraing is modified.

Related issues:

• Add assistance to detect common backwards compatibilty issues elastic-package#579
• [discuss] Backporting and testing strategies #1115

[botelastic]

Hi! We just realized that we haven't looked into this issue in a while. We're sorry! We're labeling this issue as Stale to make it hit our filters and make sure we get back to it as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1. Thank you for your contribution!