Don't show pending state when analysis has failed

[robertbrignull]

If a variant analysis fails because there are no repos to query (or the repos don't have databases) then it doesn't get as far as creating an actions workflow. This means that using the presence of that field alone is problematic for determining the status of a variant analysis.

This PR will avoid cases like:

Checklist

• CHANGELOG.md has been updated to incorporate all user visible changes made by this pull request.
• Issues have been created for any UI or other user-facing changes made by this pull request.
• [Maintainers only] If this pull request makes user-facing changes that require documentation changes, open a corresponding docs pull request in the github/codeql repo and add the ready-for-doc-review label there.

[robertbrignull]

I briefly forgot tests exist, but I'll try to write some that cover this.

[robertbrignull]

There weren't any existing tests of the logic in this component, which is understanding as it's the top-level component and there isn't much logic in it itself beyond delegating to other component. So I've added tests about showing a pending analysis and this specific case of an analysis that failed because there were no repos to query. I've avoided going further than that to avoid this PR getting out of control.