build(deps): Bump nginxinc/nginx-unprivileged from 1.26.0 to 1.27.3

Bumps nginxinc/nginx-unprivileged from 1.26.0 to 1.27.3.

---
updated-dependencies:
- dependency-name: nginxinc/nginx-unprivileged
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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