Back version of ruby to be in RVM supported set

[poloka]

Description of Changes

Back version of ruby to be in RVM supported set

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Release activity

Checklist:

Following the Contributing Guidelines

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works and they pass when merging upstream
• I have added an entry to the Changelog accordingly
• I have added my name to the CONTRIBUTORS.md
• I have squashed related commits