Remove system props replacement on EclipseLauncher

[d-gs]

Type of request

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that would cause existing functionality to change)
• [x] Refactoring
• [ ] Documentation or documentation changes

Related Issue(s)

Requires https://github.com/aposin/gem-config/pull/2

Concept

Remove the workaround to substitute the system properties on the EclipseLauncher, as it is handled by the HOCON parser by using the proper syntax.

Checklist:

• [x] All the commits are signed.
• [x] My code follows the code style of this project.
• [x] I agree with die CLA.
• [x] I have read the CONTRIBUTING docs.
• [x] I have added/updated necessary documentation (if appropriate).