Add few more tests for campaign module

[madhurgupta10]

Description
Add few more tests for campaign module

Tests performed
Tested ProdDebug on Google Pixel 2 with API level 29

[codecov-commenter]

Codecov Report

Merging #4384 (fa96346) into master (2e0f8e6) will increase coverage by 0.05%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #4384      +/-   ##
============================================
+ Coverage     10.21%   10.26%   +0.05%     
- Complexity      469      472       +3     
============================================
  Files           342      342              
  Lines         13104    13104              
  Branches       1072     1072              
============================================
+ Hits           1338     1345       +7     
+ Misses        11698    11692       -6     
+ Partials         68       67       -1     

Impacted Files	Coverage Δ	Complexity Δ
...free/nrw/commons/campaigns/CampaignsPresenter.java	66.66% <0.00%> (+13.72%)	6.00% <0.00%> (+3.00%)

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