IssueRespondedComponent: Decompose logical expressions into methods

[dingyuchen]

Addresses a task in #553

Changes:

• Logical expressions in the IssueRespondedComponent for initialising default filter has been decomposed into separate methods
• Tests have been added to check if the default filter is being initialised correctly

Proposed Commit Message:

IssueRespondedComponent: Decompose logical expressions into methods

Logic expression for initialising default filter for
IssueRespondedComponent is too long and has no tests. 

Let's
* decompose the logic expression to improve readability 
* add tests for default filter initialisation

[seanlowjk]

Just two comments wrt to the tests!

Other than that, good job! :D

[codecov-io]

Codecov Report

Merging #599 (0e74421) into master (a3959c5) will increase coverage by 0.18%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #599      +/-   ##
==========================================
+ Coverage   67.02%   67.20%   +0.18%     
==========================================
  Files          70       71       +1     
  Lines        2135     2150      +15     
  Branches      199      199              
==========================================
+ Hits         1431     1445      +14     
- Misses        663      664       +1     
  Partials       41       41              

Impacted Files	Coverage Δ
...ponse/issue-responded/issue-responded.component.ts	93.33% <100.00%> (ø)

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[seanlowjk]

Thank you for the tests and refactoring! Good work! 💯

[ptvrajsk]

LGTM 👍 Nice Job

[kkangs0226]

Other than the comments I've made, LGTM!👍

[anubh-v]

Looks good, but needs some tidying up for the test descriptions.

[anubh-v]

@dingyuchen can you make the changes? Thanks!