fix for debian testing / sid

[msielicki]

For Debian Testing and Sid ansible_distribution_major_version contains a string instead of an int

Description

Change add an additional condition to check that the Debian distribution is newer than the latest stable version.

Related Issue

#90

Types of changes

• 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 change)
• Chore (non-breaking change that does not add functionality or fix an issue)

Checklist:

• I have read the CONTRIBUTING document.
• I have run the pre-merge tests locally and they pass.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.