feat(opentelemetry-configuration): set attributes from attribute list from env variables

[maryliag]

From spec, the attribute_list should be added to attribute, but the attribute should take precedent if they exist.

For env variables, is just about adding the values from attribute list to attributes.
For config file, add the attribute list values to attributes, only if there is no attributes already.

This also fix the index file

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.16%. Comparing base (0e09680) to head (b197eea).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6043   +/-   ##
=======================================
  Coverage   95.15%   95.16%           
=======================================
  Files         316      316           
  Lines        9184     9198   +14     
  Branches     2053     2057    +4     
=======================================
+ Hits         8739     8753   +14     
  Misses        445      445           

Files with missing lines	Coverage Δ
...try-configuration/src/EnvironmentConfigProvider.ts	100.00% <100.00%> (ø)
...ntelemetry-configuration/src/FileConfigProvider.ts	94.03% <100.00%> (+0.09%)	⬆️

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.