Bump environs from 4.1.2 to 4.1.3 in /{{cookiecutter.app_name}}

Bumps [environs](https://github.com/sloria/environs) from 4.1.2 to 4.1.3.
- [Release notes](https://github.com/sloria/environs/releases)
- [Changelog](https://github.com/sloria/environs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sloria/environs/compare/4.1.2...4.1.3)

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

{{cookiecutter.app_name}}/Pipfile

@@ -41,7 +41,7 @@ Flask-Caching = ">=1.0.0"
 Flask-DebugToolbar = "==0.10.1"
 
 # Environment variable parsing
-environs = "==4.1.2"
+environs = "==4.1.3"
 
 [dev-packages]
 # Testing