chore: Enable unparam linter and cover unused *Response results

[ManavSharma142]

Fixes : #3953
I enabled the unparam linter for exported results and exercised previously unused *Response return values in tests.
For the 9 affected methods, I added testNewRequestAndDoFailure blocks to ensure the *Response path is covered.

I also updated the CI config to enable:
unparam:
check-exported: true
and modified apps_test.go accordingly.

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[ManavSharma142]

signed

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.51%. Comparing base (f32f05e) to head (d8adb5d).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3955      +/-   ##
==========================================
+ Coverage   92.45%   92.51%   +0.05%     
==========================================
  Files         203      203              
  Lines       14980    14980              
==========================================
+ Hits        13850    13858       +8     
+ Misses        927      923       -4     
+ Partials      203      199       -4     

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[gmlewis]

Thank you, @ManavSharma142!
This is very interesting and is actually highlighting a number of problems:

1. testBadOptions doesn't need to be within any table-driven tests
2. testBadOptions only needs to be called once per endpoint, with newlines for args
3. methodName should always be shared between testBadOptions and testNewRequestAndDoFailure
4. Some tests that actually take string arguments appear to be missing a testBadOptions call

Could you please investigate these issues in this repo, @ManavSharma142?

[ManavSharma142]

Thank you, @ManavSharma142!
This is very interesting and is actually highlighting a number of problems:

1. testBadOptions doesn't need to be within any table-driven tests
2. testBadOptions only needs to be called once per endpoint, with newlines for args
3. methodName should always be shared between testBadOptions and testNewRequestAndDoFailure
4. Some tests that actually take string arguments appear to be missing a testBadOptions call

Could you please investigate these issues in this repo, @ManavSharma142?

I believe a separate issue/pr is warranted, since this requires extensive refactoring across all test functions.

[gmlewis]

Thank you, @ManavSharma142!
LGTM.
Awaiting second LGTM+Approval from any other contribitor to this repo before merging.

[Not-Dhananjay-Mishra]

For consistency can we place it after staticcheck (Alphabetical order)