Handling concurrent modifications on HTTP Header Response

[fhibf]

This PR has changes to better handle changes on HTTP Headers.

Description

HTTP Headers are used in multiple scenarios:

• When reading responses from Cosmos DB.
• When consuming headers from a HTTP requests.
• When setting up a HTTP response.

Some of these scenarios raised errors, due parallel manipulations in these headers.

In this PR, there are changes to better handle HTTP Header safely, and avoid those errors.

Related issues

Addresses AB#188019.

Testing

Describe how this change was tested.

FHIR Team Checklist

• Update the title of the PR to be succinct and less than 65 characters
• Add a milestone to the PR for the sprint that it is merged (i.e. add S47)
• Tag the PR with the type of update: Bug, Build, Dependencies, Enhancement, New-Feature or Documentation
• Tag the PR with Open source, Azure API for FHIR (CosmosDB or common code) or Azure Healthcare APIs (SQL or common code) to specify where this change is intended to be released.
• Tag the PR with Schema Version backward compatible or Schema Version backward incompatible or Schema Version unchanged if this adds or updates Sql script which is/is not backward compatible with the code.
• When changing or adding behavior, if your code modifies the system design or changes design assumptions, please create and include an ADR.
• CI is green before merge
• Review squash-merge requirements

Semver Change (docs)

Patch|Skip|Feature|Breaking (reason)

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.90%. Comparing base (d0f531d) to head (ec4a9bf).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5480      +/-   ##
==========================================
- Coverage   77.20%   76.90%   -0.31%     
==========================================
  Files         978      980       +2     
  Lines       35680    35765      +85     
  Branches     5356     5364       +8     
==========================================
- Hits        27547    27504      -43     
- Misses       6803     6926     +123     
- Partials     1330     1335       +5     

see 20 files with indirect coverage changes

🚀 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.