Update README.md to include a pointer to the NGINX Community Forum

[dwmcallister]

Added a specific pointer to the Commuity Forum for additional touchpoint with NIC

Proposed changes

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that issue here in this description (not in the title of the PR).

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• [x ] I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• [x ] I have updated necessary documentation
• [x ] I have rebased my branch onto main
• [x ] I will ensure my PR is targeting the main branch and pulling from my branch from my own fork