Bump dotenv-rails from 2.5.0 to 2.6.0 (#9803)

Bumps [dotenv-rails](https://github.com/bkeepers/dotenv) from 2.5.0 to 2.6.0.
- [Release notes](https://github.com/bkeepers/dotenv/releases)
- [Changelog](https://github.com/bkeepers/dotenv/blob/master/Changelog.md)
- [Commits](https://github.com/bkeepers/dotenv/commits

)

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