Drop Git requirements specifically for Geo feature

What does this MR do?

Drops Git requirements specifically for Geo feature.

As GitLab standalone now requires Git 2.24+ (from %13.1 through %13.4), the Geo-specific requirement for Git (2.9+) is no more effective.

Does this MR meet the acceptance criteria?

Conformity

• [n/a] Changelog entry
• Documentation (if required)
• [n/a] Code review guidelines
• [n/a] Merge request performance guidelines
• [n/a] Style guides
• [n/a] Database guides
• Separation of EE specific content