Release NIC 5.4.0

[danielnginx]

Tasks

• QE sign off - ensure that we are shipping without bugs, and we have the latest base OS images
• Security sign-off - ensure that we are not shipping any fixable CVEs, and if we have CVE's they are documented, and internal security clearance is done
• Docs release notes & Changelog
• Release Operator
• Update and Test NGINX Agent
• Update and Test WAF and DOS
• Update and Test NGINX