add litserve.loops tests

[aniketmaurya]

Before submitting

• Was this discussed/agreed via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?

⚠️ How does this PR impact the user? ⚠️

No direct impact, it increases the test coverage.

GOOD:

"As a user, I need to serve models faster. This PR focuses on enabling speed gains by using GPUs"

BAD:

"This PR enables GPUs".
This is bad because the user problem is not clear... instead it just jumps to the solution without any context.

PRs without this will not be merged.

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What does this PR do?

add litserve.loops tests

PR review

Anyone in the community is free to review the PR once the tests have passed.
If we didn't discuss your PR in GitHub issues there's a high chance it will not be merged.

Did you have fun?

Make sure you had fun coding 🙃

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95%. Comparing base (5a2e8ec) to head (d1f725a).
Report is 1 commits behind head on main.

Additional details and impacted files

@@         Coverage Diff         @@
##           main   #257   +/-   ##
===================================
+ Coverage    92%    95%   +2%     
===================================
  Files        14     14           
  Lines      1082   1082           
===================================
+ Hits        999   1023   +24     
+ Misses       83     59   -24