ci: don't apply test labels if workflow was skipped

[casswedson]

Summary

None

Purpose of change

Labeling based on workflow status sure is nice, lets you know stuff
compiles or passes the styling checks, however it becomes a lil bit
noisy if the thing also adds labels on a workflow skip aka to things
that have nothing to do with compiling or styling

Describe the solution

Describe alternatives you've considered

Testing

Here I had the labeler apply the json style ok label on workflow success but don't apply the cpp style ok label on workflow skip
casswedson#13

Additional context