Update pyproject-fmt requirement from <2.5 to <2.6

Updates the requirements on [pyproject-fmt](https://github.com/tox-dev/toml-fmt) to permit the latest version.
- [Release notes](https://github.com/tox-dev/toml-fmt/releases)
- [Commits](tox-dev/toml-fmt@pyproject-fmt/2.4.0...pyproject-fmt/2.5.0)

---
updated-dependencies:
- dependency-name: pyproject-fmt
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -64,7 +64,7 @@ develop = [
   "black<25",
   "mypy<1.12",
   "poethepoet<1",
-  "pyproject-fmt<2.5",
+  "pyproject-fmt<2.6",
   "ruff<0.6",
   "validate-pyproject<0.22",
 ]