Upgrade gemnasium-maven-plugin to 0.7.0

What does this MR do?

This MR deploys a new gemnasium-maven-plugin version which updates its maven version to 3.9.6. The reasoning for releasing the plugin as a separate version and merging this change into gemnasium is because this plugin is built into the analyzer for offline mode.

What are the relevant issue numbers?

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated for GitLab EE, if necessary
• Documentation created/updated for this project, if necessary
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Job definition updated, if necessary
  • Auto-DevOps template
  • Job definition example
  • CI Templates
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer