Stopped "keyword" match from taking \n

[syko9000]

⚠️⚠️⚠️ Since we do not accept all types of pull requests and do not want to waste your time. Please be sure that you have read pull request rules:
https://github.com/louislam/dockge/blob/master/CONTRIBUTING.md

Tick the checkbox if you understand [x]:

• I have read and understand the pull request rules.

Description

The keyword match for the .env highlighter took the \n and thus prism didn't do it's line management on it and threw everything off. I checked the other regex's and this doesn't occur anywhere else.

Fixes #247 #248

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)