Bump flake8-debugger in /{{cookiecutter.app_name}}/requirements

Bumps [flake8-debugger](https://github.com/jbkahn/flake8-debugger) from 3.1.0 to 3.1.1.
- [Release notes](https://github.com/jbkahn/flake8-debugger/releases)
- [Commits](https://github.com/jbkahn/flake8-debugger/compare/3.1.0...3.1.1)

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

{{cookiecutter.app_name}}/requirements/dev.txt

@@ -11,7 +11,7 @@ pdbpp==0.10.2
 black==19.3b0
 flake8==3.7.8
 flake8-blind-except==0.1.1
-flake8-debugger==3.1.0
+flake8-debugger==3.1.1
 flake8-docstrings==1.5.0
 flake8-isort==2.7.0
 isort==4.3.21