Add new dependency scanning var for specifying the pip version

What does this MR do?

This MR adds a new variable for the dependency scanning template. This variable controls the pip version used for analyzing python projects.

Does this MR meet the acceptance criteria?

Conformity

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

Closes #12811 (closed)