Fix failing test coverage checks

[lshandross]

The test-coverage checks are currently failing (see example from recent pull request here). This may be because this package does not yet have any functions or tests.

[zkamvar]

This could be fixed by adding a function that prints out the description of the packages that are available and then testing that it works.

At the moment, this package is convenient for installing all of the packages, but it cannot yet load them. To do that, we would need to implement the tidyverse strategy of defining a hubverse_attach() function and then putting that inside of an .onAttach() function