feat(collections/unstable): support Iterable argument in dropLastWhile()

[Liam-Tait]

Create a backwards compatible unstable version of dropLastWhile() that accepts an iterable.

Slight modification to the loop to avoid the offset - 1 calculation each loop.

#5470

• Remove the test benchmark before merging

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.74%. Comparing base (ea85486) to head (2643b40).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6076      +/-   ##
==========================================
- Coverage   96.75%   96.74%   -0.01%     
==========================================
  Files         508      509       +1     
  Lines       39140    39154      +14     
  Branches     5793     5795       +2     
==========================================
+ Hits        37869    37880      +11     
- Misses       1229     1232       +3     
  Partials       42       42              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[kt3k]

LGTM. Thanks!