Merge test-suite branch to main

[caitlinch]

Complete test-suite branch on Caitlin's fork and merge to main

• Test PoolPrev() with input data checks
• Fix any PoolPrev() issues
• Test HierPoolPrev() with input data checks
• Fix any HierPoolPrev() issues
• R CMD CHECK
• Resolve ERRORS
• Resolve WARNINGS
• Resolve NOTES
• Fix broken tests
• Redo R CMD CHECK
• Pull request
• Merge branch

[caitlinch]

Due to the recursive structure of PoolPrev() and HierPoolPrev(), I exported the CheckInputData() as a function for users to apply directly. I attempted to implement within PoolPrev() and HierPoolPrev(), but the recursion limits the use of the checks. The main issue was that restricting the input data meant when the function called again, it raised an error (i.e., input data type went from data.frame to tibble) and I couldn't see a clear way to distinguish the initial and subsequent calls without adding another input variable to the functions.

There is probably a better way to implement the checks within these functions, which I leave as an exercise to the next developer!