Reuse addNextButton() for Capture location and drop pin tasks

[shobhitagarwal1612]

This PR is a pure refactor which is split from #2986 so that main logic change can be separated from refactors.

Things done:

• Adds support for hiding the next button in the base helper method
• Reuse the same function in drop pin and capture location tasks.

@anandwana001 PTAL?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.42%. Comparing base (4a5d796) to head (d3ee680).
Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #2997      +/-   ##
============================================
- Coverage     63.49%   63.42%   -0.07%     
  Complexity     1241     1241              
============================================
  Files           267      267              
  Lines          6509     6497      -12     
  Branches        911      911              
============================================
- Hits           4133     4121      -12     
  Misses         1790     1790              
  Partials        586      586              

Files with missing lines	Coverage Δ
...tion/tasks/location/CaptureLocationTaskFragment.kt	54.34% <100.00%> (-5.27%)	⬇️
.../datacollection/tasks/point/DropPinTaskFragment.kt	76.92% <100.00%> (-3.08%)	⬇️