common: Add package check for metainfo file name

[EbonJaeger]

Summary
We want to be able to catch when a package contains AppStream metainfo files that don't follow the correct naming convention. If they don't, they may not be picked up during the generation of the AppStream catalog.

Signed-off-by: Evan Maddock maddock.evan@vivaldi.net

Test Plan

1. Modify by hand the package.yml and pspec_x86_64 files for gnome-software and discover to bump the package release.
2. Run go-task check and see no warnings.
3. Modify the name of a metainfo file in one of the pspec files to be an invalid name.
4. Run go-task check and see a warning about the metainfo file name.

Checklist

• Package was built and tested against unstable
• This change could gainfully be listed in the weekly sync notes once merged
• I agree to license this contribution and all my previous contributions under the licensing terms in LICENSE.md and have the power and authority to grant those licenses.

[Jaredy899]

I think we need to add something about appstreamcli validate because I've forgotten to do this. Is this something we can add?

[EbonJaeger]

Where? That sounds outside the scope of this PR.

[clintre]

@Jaredy899 Part of the problem is that this issue this aims to resolve was not caught by appstreamcli validate