breaking: Remove verify2.Locale enum

[SMadani]

Due to the complexities of locales in Verify v2, this PR removes the hardcoded enums from VerificationRequest altogether in favour of java.util.Locale.

[codecov-commenter]

Codecov Report

Merging #499 (f4ad765) into main (1de01a9) will decrease coverage by 0.05%.
The diff coverage is 75.00%.

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #499      +/-   ##
============================================
- Coverage     94.66%   94.61%   -0.05%     
+ Complexity     2863     2862       -1     
============================================
  Files           423      422       -1     
  Lines          6949     6911      -38     
  Branches        439      440       +1     
============================================
- Hits           6578     6539      -39     
  Misses          200      200              
- Partials        171      172       +1     

Files	Coverage Δ
...com/vonage/client/verify2/VerificationRequest.java	98.43% <75.00%> (-1.57%)	⬇️