feat(gax-internal): re-export Client and ClientBuilder in http::reqwest

[olavloite]

Re-export reqwest::Client and reqwest::ClientBuilder from gaxi::http::reqwest. It does not bump the gax-internal version number, as that version has already been updated for the next release by other pull requests.

This allows client libraries to construct HTTP clients with custom connection timeouts (such as for querying the Compute Engine Metadata Service) without declaring direct dependencies on reqwest.

Needed for #6445

[gemini-code-assist]

Code Review

This pull request bumps the version of the google-cloud-gax-internal crate (and its dependency reference gaxi) from 0.7.18 to 0.7.19. Additionally, it re-exports Client and ClientBuilder from the reqwest module in src/gax-internal/src/http/reqwest.rs. There are no review comments, and I have no feedback to provide.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.37%. Comparing base (9ed9339) to head (60d9868).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6446   +/-   ##
=======================================
  Coverage   96.37%   96.37%           
=======================================
  Files         297      297           
  Lines       84017    84017           
=======================================
  Hits        80971    80971           
  Misses       3046     3046           

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[coryan]

Please revert the bumps:

git describe --tags --abbrev=0 upstream/main
git diff release-20260730 -- src/gax-internal/Cargo.toml

[coryan]

We don't need to bump this again, it was already bumped (twice) since the last release.

[olavloite]

Done