Add `hasNext` and `hasPrevious` properties

[noahpistilli]

This PR adds the properties hasNext and hasPrevious which are similar to the flask-sqlalchemy properties has_next and has_prev.

[0xTim]

Can you add some tests to this? Especially to check the boundaries/edge cases. Like count of 0, trying to pass in a page of -1 etc

[noahpistilli]

Can you add some tests to this? Especially to check the boundaries/edge cases. Like count of 0, trying to pass in a page of -1 etc

Should I add bounds to PageMetadata.page and PageMetadata.per then? Right now it will gladly accept a negative page number and a value of 0

[0xTim]

Can you add some tests to this? Especially to check the boundaries/edge cases. Like count of 0, trying to pass in a page of -1 etc

Should I add bounds to PageMetadata.page and PageMetadata.per then? Right now it will gladly accept a negative page number and a value of 0

Yes we definitely need tests and count checking for this

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (bb47433) 47.39% compared to head (affcd01) 47.52%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #482      +/-   ##
==========================================
+ Coverage   47.39%   47.52%   +0.13%     
==========================================
  Files         106      106              
  Lines        4756     4768      +12     
==========================================
+ Hits         2254     2266      +12     
  Misses       2502     2502              

Files	Coverage Δ
...luentKit/Query/Builder/QueryBuilder+Paginate.swift	80.00% <100.00%> (+5.00%)	:arrow_up: