build(deps-dev): update packaging requirement from <26.0 to <27.0

Updates the requirements on [packaging](https://github.com/pypa/packaging) to permit the latest version.
- [Release notes](https://github.com/pypa/packaging/releases)
- [Changelog](https://github.com/pypa/packaging/blob/main/CHANGELOG.rst)
- [Commits](pypa/packaging@14.0...26.2)

---
updated-dependencies:
- dependency-name: packaging
  dependency-version: '26.2'
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pyproject.toml

@@ -16,7 +16,7 @@ dev = [
 
 toxgen = [
     "jinja2",
-    "packaging<26.0",
+    "packaging<27.0",
     "pip",
     "requests",
 ]