otelconf: Increased test coverage for Prometheus-related code

[sonalgaud12]

This PR fixes #6821

• Added test for prometheusReader function for both v0.3.0 & v0.2.0

• [x] Locally tested

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 81.8%. Comparing base (a2c5420) to head (7c0fe97). :warning: Report is 1 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #7440   +/-   ##
=====================================
  Coverage   81.8%   81.8%           
=====================================
  Files        194     194           
  Lines      13362   13362           
=====================================
+ Hits       10931   10936    +5     
+ Misses      2033    2029    -4     
+ Partials     398     397    -1     

see 1 file with indirect coverage changes

:rocket: New features to boost your workflow:

• :snowflake: Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[pellared]

@sonalgaud12, are you able to address the comments?

[pellared]

@sonalgaud12, are you able to address @XSAM's comments?

[sonalgaud12]

@pellared @XSAM I have made all the changes. Can you guys review it once and let me know if anything else is required?

[sonalgaud12]

Need approval from @codeboten @MrAlias