Move defaults to script for API Fuzzing CI template

What does this MR do?

Moves variable defaults into the script section of the API Fuzzing job. This change also deprecates some variables:

• FUZZAPI_REPORT_ASSET_PATH -- Fixed to gl-assets
• FUZZAPI_REPORT -- Fixed to gl-api-fuzzing-report.json
• FUZZAPI_LOG_SCANNER -- Collecting all gl-*.log files

Additionally, the _unlicensed job has been removed. The check is now performed in the script.

Related to #327508 (closed)

CI Template

• Changes are not backwards compatible and made to latest version.
• Documentation updated removing FUZZAPI_REPORT variable from table
• Test Project:
  • Project
  • CI template
  • Job
  • 

Screenshots (strongly suggested)

No screenshot provided, the latest template versions do not show in the UX.

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
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  • I have not included a changelog entry because _____.
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• 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

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team