Add issue to troubleshooting sections for API Security

What does this MR do and why?

Document a bug in API Security and provide guidance on resolution. Information added to the troubleshooting sections of DAST API and API Fuzzing.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #345290 (closed)