fixed replacing of values using regex

[eschricker]

Fixed the env-helper-trait to replace values in .env file using regex

Description

preg_replace is used instead of str_replace to support regex.

Checklist:

• [ ] I've added tests for my changes or tests are not applicable
• [ ] I've changed documentations or changes are not required
• [ ] I've added my changes to CHANGELOG.md

[Messhias]

Look good, I believe it doesn't need test, or we should cover it too?

[mfn]

This is now part of 2.0.0-RC1. If you have time and can give it a spin before we push out 2.0.0, that would be great!