Improve visibility of Project Vulnerabilities API doc

Problem to solve

According to customer-based feedback in this thread, customers find it difficult to locate docs for the Project Vulnerabilities API in the:

• Global nav bar
• List of project resources
• Projects API
• Vulnerabilities and Vulnerability Findings API docs, which don't provide this information.

The Vulnerabilities API has since been deprecated, replaced with GraphQL.

As this feedback was raised ~ 11 months ago, need to see if this is still an issue or have there been changes to the global nav and documentation that have corrected this.

Proposal

MVC:

• Update table in Resources so that project vulnerabilities is in alphabetical order.
• Add a link to Project Vulnerabilities API doc in the Projects page, much in the same way as the Branches section. This will obviously make the right-nav bar longer, but it's a suitable MVC to solve the frustration of not finding anything about Project Vulnerabilities of the Projects page.

Other links/references

Related to #270396 (closed)