fix: Fixed NIM pattern install.sh script and NGC Key instruction

[hustshawn]

What does this PR do?

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• Updated the logic in install.sh script. When customer using NIM pattern, should not check the HuggingFace token for Triton pattern
• Updated the NVIDIA NGC API Key instructions. More detailed instruction added, and emphasized the requirement for NVIDIA AI Enterprie registration. It is mandatory for using NIM, but it's not even clearly addressed in the current NIM doc.
• Also updated the website doc to make it make it clear for customer to follow.

Motivation

Fixed NIM pattern install.sh script and NGC Key instruction

More

• Yes, I have tested the PR using my local account setup (Provide any test evidence report under Additional Notes)
• Mandatory for new blueprints. Yes, I have added a example to support my blueprint PR
• Mandatory for new blueprints. Yes, I have updated the website/docs or website/blog section for this feature
• Yes, I ran pre-commit run -a with this PR. Link for installing pre-commit locally

For Moderators

• E2E Test successfully complete before merge?

Additional Notes