Rename vulnerability projects queries

What does this MR do?

This MR renames the GraphQL queries used on the group-level and instance-level vulnerability reports, to make them clearer what they're for and to make debugging easier. This is refactor work only.

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have included a changelog entry.
  • I have not included a changelog entry because this is refactor work.
• [-] Documentation (if required)
• Code review guidelines
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• [-] Style guides
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• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done