chore: Bump the testing group across 1 directory with 2 updates

Bumps the testing group with 2 updates in the / directory: [pytest](https://github.com/pytest-dev/pytest) and [pytest-cov](https://github.com/pytest-dev/pytest-cov).


Updates `pytest` from 9.0.2 to 9.0.3
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@9.0.2...9.0.3)

Updates `pytest-cov` from 7.0.0 to 7.1.0
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v7.0.0...v7.1.0)

---
updated-dependencies:
- dependency-name: pytest
  dependency-version: 9.0.3
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: testing
- dependency-name: pytest-cov
  dependency-version: 7.1.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: testing
...

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

Author: dependabot[bot]

pyproject.toml

@@ -46,8 +46,8 @@ include = ["src/fluxopt_plot/", "LICENSE", "README.md"]
 dev = [
     "mypy==1.19.1",
     "pre-commit==4.5.1",
-    "pytest==9.0.2",
-    "pytest-cov==7.0.0",
+    "pytest==9.0.3",
+    "pytest-cov==7.1.0",
     "ruff==0.15.5",
 ]
 docs = [