docs: update README to provide users with guidance to turn on PQC encryption

[danieljbruce]

Description

Users need to know that they must upgrade their Node version to 22.20 or higher to ensure their network traffic is secure against post-quantum decryption algorithms like Shor's algorithm. So this PR updates the README to ensure customers are well informed.

Impact

Informs users so that they can better encrypt their network traffic.

[gemini-code-assist]

Code Review

This pull request updates the README.md file to include information about network traffic security against post-quantum decryption algorithms. Feedback indicates a typo in the Node.js version (should be 22.2.0 instead of 22.20) and notes that because this file is auto-generated, the change should be made in the upstream generator or template rather than directly in this file.

[gemini-code-assist]

Node.js enabled the post-quantum key agreement algorithm (X25519Kyber768Draft) by default in version 22.2.0, not 22.20. Please update this version reference in the upstream generator or template rather than editing this auto-generated file directly, as manual changes will be overwritten.

References

1. Do not manually edit auto-generated files to fix typos or make other changes, as these edits will be overwritten during the next regeneration. Instead, apply the fixes upstream in the generator or templates.

[danieljbruce]

This statement doesn't appear to be true. I tried this version of Node out on main...pqc-version-check-again and the test fails so I think 22.20 is the right version.

[pearigee]

Should we give it its on heading?

I think the key things people need to know:

• What is the minimum node version?
• Is it enabled automatically? If not, how do I turn it on?
• If automatic, what triggers it?

Suggestion (feel free to ignore/rewrite accordingly):

## Post-quantum Cryptography

A minimum Node version of >=22.20 is required for post-quantum cryptography to be used. If using a supported runtime, traffic will be automatically upgraded when [condition].

[danieljbruce]

Should we give it its on heading?

I think the key things people need to know:

• What is the minimum node version?
• Is it enabled automatically? If not, how do I turn it on?
• If automatic, what triggers it?

Suggestion (feel free to ignore/rewrite accordingly):

## Post-quantum Cryptography

A minimum Node version of >=22.20 is required for post-quantum cryptography to be used. If using a supported runtime, traffic will be automatically upgraded when [condition].

I modified this slightly just to capture the fact that it is the client library requests specifically that are secure when the user is importing a client library.