join_contexts failing on `vanderMoezel_1987` in v 4.2.0

[ehwenk]

the join_contexts function is failing at vanderMoezel_1987 (v4.2.0), because there are two entries for a context that map to the same context property value - and therefore break the function the second place pivot_wider is used:

dataset_id        link_id           link_vals `time to flowering type`
  <chr>             <chr>             <chr>     <chr>                   
1 vanderMoezel_1987 entity_context_id 01        from seed               
2 vanderMoezel_1987 entity_context_id 03        from resprouting        
3 vanderMoezel_1987 entity_context_id 04        unknown                 
4 vanderMoezel_1987 entity_context_id 02        unknown  

I've fixed this in the current austraits.build repository, but in the meantime, vanderMoezel_1987 needs to be added flagged as a problem study within the join_contexts function. (Meanwhile Hall_1981 is no longer a problem study in v4.2.0.)

@yangsophieee and I decided today to add tests to traits.build that ensure the austraits functions work as each new dataset is added to ensure these problems stop surfacing after releases!