Update pyupgrade requirement from ~=3.3 to ~=3.15

Updates the requirements on [pyupgrade](https://github.com/asottile/pyupgrade) to permit the latest version.
- [Commits](asottile/pyupgrade@v3.3.0...v3.15.0)

---
updated-dependencies:
- dependency-name: pyupgrade
  dependency-type: direct:development
...

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

requirements-dev.txt

@@ -4,7 +4,7 @@ black==23.11.0
 codespell~=2.2
 isort~=5.10
 pydocstyle~=6.1
-pyupgrade~=3.3
+pyupgrade~=3.15
 yamllint~=1.28
 PyGithub~=2.1
 pre-commit~=3.5