fix: ds getting false positives for special variables

[CLHatch]

ds was detecting variables such as GLUETUN_ENVIRONMENT_VPN_PORT_FORWARDING as being a GLUETUN_PORT_XXXX variable.

Pull request

Purpose
Describe the problem or feature in addition to a link to the issues.

Approach
How does this change address the problem?

Open Questions and Pre-Merge TODOs
Check all boxes as they are completed

• Use github checklists. When solved, check the box and explain the answer.

Learning
Describe the research stage
Links to blog posts, patterns, libraries or addons used to solve this problem

Requirements
Check all boxes as they are completed

• These changes meet the standards for contributing.
• I have read the code of conduct.