Test/application: refactoring mock classes

[saksham-gt]

Declaring all mock classes in test utilities.

[codecov[bot]]

Codecov Report

Merging #250 (354fe58) into development (e7a984d) will increase coverage by 1.84%. The diff coverage is 14.28%.

@@              Coverage Diff               @@
##           development    #250      +/-   ##
==============================================
+ Coverage         7.90%   9.75%   +1.84%     
==============================================
  Files              122     122              
  Lines             3401    3404       +3     
==============================================
+ Hits               269     332      +63     
+ Misses            3132    3072      -60     

Impacted Files	Coverage Δ
lib/presentation/home/home_screen.dart	5.55% <0.00%> (ø)
...ib/presentation/shared_widgets/photo_selector.dart	0.00% <0.00%> (ø)
lib/domain/user/user.dart	100.00% <100.00%> (ø)
lib/application/user/profile/profile_state.dart	33.33% <0.00%> (+16.66%)	:arrow_up:
lib/application/user/profile/profile_bloc.dart	23.07% <0.00%> (+23.07%)	:arrow_up:
...ib/application/user_details/user_details_bloc.dart	91.66% <0.00%> (+91.66%)	:arrow_up:
lib/domain/core/errors.dart	100.00% <0.00%> (+100.00%)	:arrow_up:
lib/domain/auth/value_objects.dart	100.00% <0.00%> (+100.00%)	:arrow_up:
lib/domain/core/value_objects.dart	100.00% <0.00%> (+100.00%)	:arrow_up:
lib/domain/auth/value_validators.dart	100.00% <0.00%> (+100.00%)	:arrow_up:
... and 1 more

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[Xazin]

Merge conflicts - needs rebase

[Xazin]

@glitchpop-frenzy 👀

[saksham-gt]

Noted, will do it this week! 😄