fix(deps): update module google.golang.org/grpc to v1.69.4

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
google.golang.org/grpc	v1.69.2 -> v1.69.4

---

Release Notes

grpc/grpc-go (google.golang.org/grpc)

v1.69.4: Release 1.69.4

Compare Source

Bug Fixes

• rbac: fix support for :path header matchers, which would previously never successfully match (#​7965).

Documentation

• examples/features/csm_observability: update example client and server to use the helloworld service instead of echo service (#​7945).

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about these updates again.

---

• If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.2%. Comparing base (8c3d01e) to head (435798d).
Report is 1 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #6159   +/-   ##
=====================================
  Coverage   82.2%   82.2%           
=====================================
  Files        273     273           
  Lines      23674   23674           
=====================================
+ Hits       19476   19478    +2     
+ Misses      3851    3849    -2     
  Partials     347     347           

see 1 file with indirect coverage changes