feat: add list of NGINX alerts in XC

[mjang]

Proposed changes

Include list of NGINX Alerts that may appear

Internal link

Specifically

HighCVENGINX
MediumCVENGINX
LowCVENGINX
SecurityRecommendationNGINX
OptimizationRecommendationNGINX
BestPracticeRecommendationNGINX
NGINXOffline
NGINXUnavailable
NewNGINX

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• I have read the contributing guidelines
• I have signed the F5 Contributor License Agreement (CLA)
• I have rebased my branch onto main
• I have ensured my PR is targeting the main branch and pulling from my branch from my own fork
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• If the change involves potentially sensitive changes¹, I have assessed the possible impact
• If applicable, I have added tests that prove my fix is effective or that my feature works
• I have ensured that existing tests pass after adding my changes
• If applicable, I have updated README.md

Footnotes

1. Potentially sensitive changes include anything involving code, personally identify information (PII), live URLs or significant amounts of new or revised documentation. Please refer to our style guide for guidance about placeholder content. ↩

[github-actions]

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[travisamartin]

Approved w/ suggested edits.

[mjang]

Hindsight, I should have left this in Draft first... Thank you for your patience, @travisamartin .

[mjang]