Add installation tests for [next] packages

What

We add installation tests for next packages

Depends on : !13697 (merged)

Why

We need to test both current and next packages for installability

How

We leverage the apt repository introduced in !13697 (merged) and we check if the packages can be installed using apt

Manually testing the MR

Check if the pipeline completes and the packages are correctly installed.

Locally you can add the repository as in !13697 (merged) and check if the packages can be installed correctly on your machine. Note that you should choose the packages for your release/distribution. Using packages for a different distribution will probably produce dependency errors.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR