this function's purpose is to take a list of dump pathnames and return a dictionary of those pathnames keyed by generic dump name.  A better test would be to use pathnames instead of base filenames:  
```'/some/random/path/that/has/no/relevance/6611a662-e70f-4ba5-a397-69a3a2121129.dump'```
should produce a corresponding element in the return dict of 
```'upload_file_minidump': '/some/random/path/that/has/no/relevance/6611a662-e70f-4ba5-a397-69a3a2121129.dump'```